B767 ATA 21 Student Book

7/21/2019 B767 ATA 21 Student Book

1/131

TRAINING MANUALFOR TRAINING PURPOSES ONLY

B767-3S2F ATA 21-00 Page - 1 4/25/13 EFF - ALL

AIR CONDITIONING CH 21


2/131



ATA 21 A IR CONDITIONING TABLE OF CONTENTS:

INTRODUCTION.................................................................................... 4 AIR FLOW GENERAL DESCRIPTION...................................................6

CONTROL GENERAL DESCRIPTION.................................................. 8

FLIGHT COMPARTMENT CONTROLS AND INDICATIONS...............10CONTROLLER LOCATION................................................................. 12PACK COMPONENT LOCATION ....................................................... 14PACK SCHEMATIC............................................................................. 16FLOW CONTROL AND SHUTOFF VALVE......................................... 18LOW LIMIT CONTROL VALVE ........................................................... 20TEMPERATURE CONTROL VALVE .................................................. 22RAM AIR.............................................................................................. 24HEAT EXCHANGERS......................................................................... 26

AIR CYCLE MACHINE ........................................................................ 28WATER EXTRACTOR......................................................................... 30WATER SPRAY NOZZLE ................................................................... 32REHEATER ......................................................................................... 34CONDENSER...................................................................................... 36SENSORS AND SWITCHES............................................................... 38CABIN AIR SUPPLY CHECK VALVE ................................................. 40PACK CONTROL COMPONENTS...................................................... 42TEMPERATURE CONTROL GENERAL DESCRIPTION ................... 44ZONE TEMPERATURE CONTROLLERS........................................... 46TEMP PRSOV ..................................................................................... 48TRIM AIR MODULATING VALVE ....................................................... 50DUCT/ZONE TEMP SENSORS, TEMP BULBS, OVHT SWITCHES . 52FWD CARGO TEMP SENSORS, OVHT SWITCH AND TEMP BULB 54

MAIN AIR DISTRIBUTION .................................................................. 56FLIGHT COMPARTMENT AIR DISTRIBUTION ................................. 58BULK CARGO VENT COMPONENTS................................................ 60FWD CARGO VENT ........................................................................... 62LAV/GALLEY DUCT VENTILATION ............ ....................................... 64HEATING INTRODUCTION ................................................................ 66FWD CARGO COMP HEATING INTRODUCTION ............................. 68FWD CARGO COMP HEATING VALVES AND TEMP SWITCHES... 70

AFT/BULK CARGO COMPARTMENT HEATING .............................. 72CARGO COMP HEATING OPERATION ............................................ 74FOOT AND SHOULDER AIR SUPPLY HEATERS............................. 76FORWARD DOOR AREA HEATER .................................................... 78

EQUIPMENT COOLING GENERAL DESCRIPTION.......................... 80FWD AND AFT EQUIPMENT COOLING INTRODUCTION................ 82

EQUIPMENT COOLING SYSTEM SCHEMATIC................................ 84EQUIPMENT COOLING CONTROL PANELS .................................... 86EQUIPMENT COOLING SYSTEM COMPONENTS ........................... 88EQUIPMENT COOLING SYSTEM COMPONENTS (CONT).............. 90EQUIPMENT COOLING SYSTEM FWD EQUIP SYSTEM ................. 92

GROUND EXHAUST VALVE .............................................................. 94EQUIPMENT COOLING INBOARD VALVES...................................... 96EQUIPMENT COOLING MANIFOLD INTERCONNECT VALVE ........ 98EQUIPMENT COOLING SMOKE CLEARANCE VALVE .................. 100

EQUIPMENT COOLING SMOKE DETECTION................................. 102 EQUIPMENT COOLING MONITOR SYSTEM......................................104

CABIN PRESSURE CONTROL INTRODUCTION ............................ 106CABIN ALTITUDE CONTROL PANEL.............................................. 108CABIN PRESSURE OUTFLOW VALVE............................................. 110

AUTOMATIC PRESSURE CONTROLLER.........................................112 AUTOMATIC PRESSURE CONTROLLER INPUTS...........................114 AUTOMATIC PRESSURE CONTROLLER OUTPUTS.......................116

AUTOMATIC PRESSURE CONTROLLER FAULTS...........................118 AUTOMATIC PRESSURE CONTROLLER BITE................................120

POSITIVE PRESSURE RELIEF VALVE............................................ 122NEGATIVE RELIEF DOORS...............................................................124

CABIN PRESSURE INDICATION.......................................................126CABIN PRESSURE ALTITUDE WARNING........................................128

CABIN ALTITUDE WARNING.............................................................130
http://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdfhttp://../Documents/21/67-21-20.pdf


3/131



STUDENT NOTES:


4/131



AIR CONDITIONING - INTRODUCTION

General

The air conditioning system controls the interior environment of the airplane for

these areas:

Flight crew Passengers Forward cargo compartment Equipment

The air conditioning system includes these subsystems:

Cooling Temperature control Distribution Heating

Abbreviations and Acronyms

A/C - AIR CONDITIONING ACM - AIR CYCLE MACHINE AGS - AIR GROUND SYSTEM APC - AUTOMATIC PRESSURE CONTROLLERCAPT - CAPTAINCKT - CIRCUITCLG - COOLING

CTRL - CONTROLECS - ENVIRONMENTAL CONTROL SYSTEMEICAS - ENGINE INDICATION AND CREW ALERTING SYSTEMEQPT - EQUIPMENTEXH - EXHAUSTF/O - FIRST OFFICERFWD - FORWARDGLY - GALLEYHTR - HEATERMEC - MAIN EQUIPMENT CENTERMGMT - MANAGEMENTOVHT - OVERHEATPFCAC - PACK FLOW AND CARGO AIR CONDITIONING CONTROLLER

PNL - PANELPRSOV - PRESSURE REGULATING SHUTOFF VALVEPWR - POWERRECIRC - RECIRCULATIONRLY - RELAY

SNSR - SENSORSOV - SHUTOFF VALVESTBY - STANDBYTAT - TOTAL AIR TEMPERATURETCV - TEMPERATURE CONTROL VALVETEMP - TEMPERATUREUTIL - UTILITYVLV - VALVEWOW - WEIGHT-ON-WHEELSZTC - ZONE TEMPERATURE CONTROLLER


5/131



AIR CONDITIONING - INTRODUCTION


6/131



AIR CONDITIONING - AIR FLOW GENERAL DESCRIPTION

Purpose

The air conditioning system controls the temperature and humidity in theairplane. It controls the amount of airflow into the airplane.

System Description

Bleed air to the airplane air conditioning system is from the engines or the APU.Conditioned air may be from a dedicated ground air conditioning cart. Bleedair is also used to heat these areas:

Forward Cargo Aft Cargo Bulk Cargo

Cooling System

These areas receive temperature controlled air:

Flight deck Forward cargo compartment Cabin compartment zone

The temperature in these zones is controlled from the flight deck with thetemperature control panels. The temperature in each zone is controlled by theaddition of hot bleed air (trim air) to the pack conditioned air that goes to eachzone.

Distribution System

The distribution system delivers fresh air to the temperature controlled zones.These are the components in this system:

Air Conditioning ducts Ventilation systems

The air conditioning ducts distribute conditioned air from the mixed manifold tothe flight deck, galley, and lavatory. A separate duct system removes air from

the galley, lavatory, and the aft equipment rack. The equipment/lavatory/galleyventilation system removes air from the lavatory and galley areas. It bringsequipment cooling air through the aft equipment rack. The ventilation systemalso brings flight deck and compartment air across zone temperature sensors.The bulk cargo ventilation system supplies cabin air to the bulk cargocompartment. The system operates when selected from the flight deck.

Heating Systems

These two heating systems are used on the airplane:

Supplemental Heating Cargo Heating

Supplemental heating goes to the flight compartment. The flight compartmenthas electrically operated in-line heaters in the air conditioning ducts. Theseprovide air to the rudder pedal area and the side windows. The crewcompartment has the same type of in-line heater. This provides warm air to thecrew entry door area.

A cargo heating system gives warm air to the forw ard, aft, and bulk cargocompartments. The three cargo compartments are controlled independently.They operate when selected from the flight deck P5 panel. All three systemsuse these to heat the compartments:

Two valves Temperature switches Bleed air from the pneumatic distribution

Forward Cargo Ventilation System

The forward cargo ventilation system makes sure cabin air provided to thecompartment is exhausted overboard. This system has several modes ofoperation that will be covered later in this section.


7/131



AIR CONDITIONING - AIR FLOW GENERAL DESCRIPTION


8/131



AIR CONDITIONING - CONTROL GENERAL DESCRIPTION

General

These flight deck panels control the air conditioning and heating systems:

Air conditioning (A/C) panel Cargo heat panel Bulk cargo heat panel Forward cargo air conditioning panel Crew foot and shoulder heater

These components in the MEC control the functions of the A/C system:

Two pack temperature controllers Zone temperature controller Left pack flow and cargo A/C controller Right, left, and center ECS fan control cards Standby pack temperature controller Right pack flow control card Right and left pack backup temperature control cards

Pack Temperature Controller

The pack temperature controllers control the temperature of the air delivered tothe mix manifold through these components:

Temperature control valve Ram air inlet door Ram air exhaust door

Zone Temperature Controller

The zone temperature controller regulates the temperatures in the flight deck,and the forward and aft cargo zones. It does this with a pack demand signalto the pack temperature controller and by control of the zone trim air modulatingvalves.

Left Pack Flow and Cargo A/C Controller

The left pack flow and cargo A/C controller (PFCAC) controls the forward cargo A/C through these components:

Cargo A/C shutoff valve Forward cargo heat shutoff valve Cargo exhaust valve Cargo ground exhaust valve Cargo ground exhaust backup valve High flow command to the left pak

Left, Center, and Right ECS Fan Control Cards

The ECS fan control cards control these fans:

Lav/galley ventilation fans

Standby Pack Temperature Controller

The standby pack temperature controller regulates pack temperature outputthrough the low limit valve.

Left and Right Pack Backup Pack Temperature Control Cards

These cards control these components:

Left and right ram air inlet and exhaust door actuators

Left and right pack temperature control valves

Right Pack Flow Control Card

The right flow control card provides control for the right pack flow control andshutoff valve. The card provides these commands to its valve:

ON OFF HI FLOW LO FLOW

The card also monitors the air conditioning system for overheat conditions for itspack.


9/131



IfCONTROLLER FAULT temp ON replace controller

When all GO (green) press RESET to clear memory

Ifany lamp does not light replace this controller

ACTRACTR

MIX MANF

PRESS/

VERIFYBIT FLIGHTSPREVIOUS RESET

FAULTS

LOW

VALVECONTFLOW

VALVELIMITOUTLET

RAM

VALVE TEMPCONT

COMPRESSOR

FAULTCONTROLLER

.

.

.

.

.

3

2

ON THIS CONTROLLERSet PACK SELECTORS to AUTO

Ateach positionwaitfor GO(green)or FAULT(red)lamp

AT FLIGHT DECK

IfFault (red) replace unit indicated and repeat Verify

Press all three test buttons in sequence indicated

Push PRESS/TEST for lamp check

1

PACK TEMPERATURE CONTROLLERBITE INSTRUCTIONS

INLETRAM

SWITCHALTITUDE

ZONESENSORSENSOR SENSOR

PACK SENSOR

TEST

GO

NORMBULK CARGO HEAT

VENT

Set all SELECTORS to AUTO

Press all three t est buttons in sequence indicated.

When all GO (green) press RESET to clear memory. IfFAULT (red) replace unit indicated and repeat VERIFY

3

2 AT FLIGHTDECK 1

conditioning faults not indicated on this controller Check EICAS maintenance messages for CARGO

For forward cargo A/C option

CABIN ZONE TEMPERATURE CONTROLLERBITE INSTRUCTIONS

PRESS/

VERIFY

FAULTS

RESETBIT

GO

TEST

FLIGHTSPREVIOUS

Ifany lamp does not light replace this controller

At each position wait for GO (green) or FAULT (red) lamp

IfCONTROLLER LAMP is ON replace controller.

Select FWD CARGO A/C ON.ON THIS CONTROLLER

Push PRESS/TEST for lamp check

FAULTCONTROLLER

CARGO

AUXFWD

MIDAUX

CARGO

AUXFWD

MIDAUX

VALVE TRIMDUCT

SENSORZONE

SENSORSELECTOR

BULK CARGO HEAT/VENTILATIONCONTROL PANEL

SUPPLEMENTAL

HEAT CONT PNL

CONTROLLERAUX ZONE TEMP

STBY PACK

PACK TEMP

NOGO

GO

POSITION 1RETURN TEST SWITCH TO

WAIT FOR STEADY LIGHT INDICATIONEACH POSITION,PRESS KNOB AND

FAULTY UNITIF NO GO STOP TEST, REPLACE

ROUTE TEST SWITCH CLOCKWISE IN2.ONTHIS CONTROLLER

SET PACK SELECTORS TO STANDBY-N1.ATFLI GHTDECK

BITE INSTRUCTIONSPACKSTANDBYCONTROLLER

RIGHT PACK LEFT PACK

1

23 4

5

6

7COMPSENSOR

SENSORPACK

CONTROLLER (2)

TEMP CONTROLLER

L ECS FANCTRL CARD

R ECS FANCTRL CARD

R PACK BACKUP TEMP CTRL CARD

L PACK BACKUP TEMP CTRL CARD

R PACK FLOWCTRL CARD

P50 CARD FILE

C ECS FANCTRL CARD

LOWHI

OFF

FOOT

HEATERS

SHOULDER

NOFFAUTO

W YB

TS

COMPTTEMP

OVHT

ON

OVHT

ONON

BULK AFTFWD

OVHT

CARGO HEAT

TEMPCONTROL

RLPACK PACK

INOPINOP

RESET

INOP

OFFPACK

TRIMAIR

FLTDECK

INOP

OFFPACK

RESET

OFF

ON

INOP

WC

NOFFAUTO

AUTO

OFF WC

AUTO

OFF WC

AFTCABFWDCABAUTO

MAN WC

W YB

TS

FWDCARGOAIRCOND AUTO

OFF

INOP

FAULT

WC

AIR CONDITIONINGCONTROL PANEL (P5)

L PACK FLOW AND

SERIAL NO.

BOEING

PACK FLOW CARGO ACCONTROLLER MODULE

PART NO.285T1150-

CARGO A/C CONTROLLER

DECK FLIGHT

VERIFYBIT PREVIOUSFLIGHTS

FWDZONE

12

3

SELECTOR

CABINZONE TEMPERATURECONTROLLER

WhenallGO (green)pressRESET toclearmemory.If FAULT (red)replaceunit indicatedandrepeat VERIFY. Ateach position waitforGO (green)or FAULT (red)lamp.

Push PRESS/TEST for lampcheck.ON THISCONTROLLER SetallSELECTORS toAUTO. If VALVE isfaulty replaceandretest. CheckTRIM VALVES bymanually operatingSELECTORS.AT FLIGHTDECK If CONTROLLER LAMPis ONreplace controller.

ZONEAFT

Pressallthree testbuttonsinsequence indicated. If any lampdoesnot lightreplace thiscontroller.

SENSORZONE

SENSORDUCT TRIM

VALVE

TEST

GO

FWDZONE

FAULTS

PRESS/

CONTROLLERFAULT

BITEINSTRUCTIONS

AFTZONE

RESET

FLIGHTDECK

ZONE TEMPERATURECONTROLLER

MAIN DECK TEMP SEL

ANIMAL/NORMPERISHABLE

TEMP SELECTORP-61 PANEL

AIR CONDITIONING - CONTROL GENERAL DESCRIPTION


10/131



AIR CONDITIONING - FLIGHT COMPARTMENT CONTROLS AND INDICATIONS

General

These flight compartment panels give control of the air conditioningsubsystems:

A/C panel on the P5 overhead panel Cargo heat panel on the P5 Bulk cargo heat/vent panel on P61 Crew supplemental heating panels

Purpose

The A/C control panel does these things:

Puts on the packs Puts on the trim air system Controls flight compartment and main cabin compartment temperature Does a reset of pack malfunctions

Three alternate-action switches on the cargo heat control panel control theforward, aft, and bulk cargo compartment heating systems.

The bulk cargo norm/vent heating panel controls more heating of the bulk cargoarea for animal carriage.

The captain and F/O heating control panels let the flight crew select more heatfor their shoulders and feet.


11/131



COMPT TEMP

Y

S T

BYW

FWD CAB AFT CAB

AUTOOFF N

RESET PACK OFF

INOP

INOP INOP

PACK R

TEMP CONTROL

S T

BW

AUTOOFF

C WMAN

AUTO

N

C W

INOP

ON

OFF

PACK OFF

INOP

FLT DECK

TRIM AIR

RESET

PACK L

C WMAN

AUTO

C WMAN

AUTO

INDICATOR

SELECTOR TEMPERATURECABIN ZONE

TEMPERATURECOMPARTMENT

INDICATORPOSITION TRIM VALVE

LIGHTZONE INOP

SW LIGHT TRIM AIR

SELECTORPACK CONTROL

SW LIGHTPACK RESET

AIR CONDITIONING CONTROL PANEL

FWD AFT

ON

OVHT

ON

OVHT

CARGO HEATBULK

ON

OVHT

BULK CARGO

HEATING PANEL

NORMBULK CARGO HEAT

VENT

P13 (CAPT), P14 (F/O) PANEL

LOWHI

OFF

FOOT

HEATERS

SHOULDER

AIR CONDITIONING - FLIGHT COMPARTMENT CONTROLS AND INDICATIONS


12/131



AIR CONDITIONING - CONTROLLER L OCATION

General

These controllers are on the E3 rack:

Zone temperature controller Left pack temperature controller Right pack temperature controller Standby pack temperature controller


13/131



AIR CONDITIONING - CONTROLLER LOCATION


14/131



AIR CONDITIONING - PACK COMPONENT LOCATION

General

The cooling packs are located in the unpressurized area between the main

wheel wells and forward cargo compartment. The cooling packs are identicalwith two exceptions.

The ducting from the air supply system to the primary heat exchangers isdifferent.

The trim air system components, pneumatic ground connectors, groundcon ditioned air connector and altitude switch are located only in the left airconditioning bay.

The Flow Control Valves are outboard of each pack.

With the exception of the cabin air supply check valve, all components areaccessible thru the air conditioning bay door. The access panel forward of thebay door and adjacent to the keel beam must be lowered to access the checkvalve.

Cooling Pack

The system operates from a source of preconditioned (precooled and pressureregulated) engine or APU bleed air supplied to the Flow Control And ShutoffValve which regulates the amount of air to the Cooling Pack. The Cooling Packuses Heat Exchangers enabled by the Ram Air System to remove heat from the

air. Air conditioning is accomplished by a bootstrap Cooling Pack utilizing athree wheel Air Cycle Machine. A high pressure Water Separation Systemremoves moisture from the air. A Pack Temperature Controller providesautomatic control of the Cooling Pack output temperature and fault monitoringof line replaceable units. A Standby Temperature Controller provides standbycontrol of the Cooling Pack. Various sensors and switches provide feedback tothe controllers and temperature protection for the Cooling Pack.


15/131



AIR CONDITIONING - PACK COMPONENT LOCATION


16/131



AIR CONDITIONING - PACK SCHEMATIC

Air Supply

Preconditioned engine bleed air or APU bleed air passes through the flow

control and shut-off valve which regulates airflow into the pack on either anormal or high flow schedule. It also functions as a shut-off valve. The airinitially enters the pack at the primary heat exchanger.

Compression

The air passes through the primary heat exchanger where it is cooled by ramair. It then enters the compressor section of the air cycle machine where itspressure and temperature is increased. The compressor discharge air is cooledby ram air in the secondary heat exchanger and then enters the reheater.

High Pressure Water SeparationThe air passes through the reheater hot side and is cooled by transferring heatto the cooler air passing through the cold side. The function of the reheater is tominimize the temperature difference between the secondary heat exchangeroutlet and the turbine inlet, thereby reducing the heat needed to be added topack discharge air. After leaving the reheater, the air passes through thecondenser where further temp reduction takes place. Lowering it to the levelrequired for moisture condensation. The air is cooled in the condenser by coldturbine exhaust air. Condensed moisture droplets then are removed by aninertial process in the water extractor. Removed at high pressure by theextractor and at another location on the secondary heat exchanger outlet duct,

the water is routed to the water spray injector where it is sprayed into the ram airinlet for the primary/secondary heat exchangers. The spray evaporating coolsthe ram air and increases system cooling capacity. The dry air leaving theextractor is heated again, as earlier mentioned, in the second pass through thereheater, recovering the energy that normally would be added to the turbineexhaust in the cold side of the condenser.

Expansion

After passing through the reheater, the dry air enters the turbine section of theair cycle machine. The air cycle machine has three rotating sections: a

compressor, a turbine, and a fan - all mounted on a common shaft supported byair bearings. In expanding through the turbine, the air delivers the power to

drive the compressor and fan. The energy lost from the turbine airflow causes atemperature reduction resulting in turbine discharge air well below ram airtemperature.

The cold turbine discharge air passes through the passages of the condenseron its way to the cabin and causes water condensation of bleed air leaving thereheater. In expanding through the turbine, turbine discharge air temperaturecan go below 32 of (0 oc). The large temperature drop may cause any moisturecondensation to form ice at the cold air face of the condenser. This is preventedby supplying warm air through de-icing passages in the face of the core, andpassing hot air into a anti-ice muff located at the cold air inlet to the condenser.Warm air for the core face is supplied from the compressor outlet.


17/131



AIR CONDITIONING - PACK SCHEMATIC


18/131



AIR CONDITIONING - FLOW CONTROL AND SHUTOFFVALVE

Purpose

The flow control and shutoff valve (FCSOV) controls the amount of airflow intothe airplane by control of the flow into the packs from the pneumatic distributionsystem. The flow control system has two flow control and shutoff valves, a flowcontrol logic card for the right pack, and a pack flow and cargo A/C controller for the left pack.

Location

The FCSOVs are in the bleed air supply pneumatic ducting that supplies air tothe packs. Each valve is outboard of its respective pack. The left FCSOV isoutboard of the left pack high pressure water separation components. The rightvalve is outboard of the right pack air cycle machine. Access is through thepack bay access doors. The pack doors are the snap-latch type.

Physical Description

The FCSOV is pneumatically operated and electrically enabled and controlled.The valve disk is spring-loaded to the closed position. The valve body is aventuri with two sensing probes, one in the inlet and the second in the venturithroat. These components are used to control the valve:

Solenoid B, latching type, gives ON/OFF control of the valve and may bemanually operated using the small manual control rod

Solenoid A, non-latching, gives a higher airflow schedule though the valve Solenoid S, non-latching, closes the valve on the right pack and reduces

flow on the left pack during main deck cargo smoke Electromagnetic control valve is used to decrease the high flow schedule

A limit switch gives valve closed information.

Maintenance Practice

You can manually operate the flow control valve for these conditions:

One FCV does not operate in the closed position if the airplane altitude isless than 35,000 feet, and the other pack low limit valve operates correctly

HI FLOW mode does not operate for one pack if the other pack HI FLOWMODE operates normally

For an electrical failure, you can operate the FCV by the manual control rod onsolenoid valve B. Pull the rod to select the OFF mode for the FCSOV.

If there is a pneumatic failure in the valve, you can lock the valve closed. Youturn an actuator nut on the manual override valve clockwise to seal off the servopressure to the actuator and open the actuator to ambient. When you turn thenut, the valve disc alsomoves closed.

CAUTION: DO NOT USE EXCESSIVE FORCE ON THE MANUAL ACTUATOR NUT. IF RESISTANCE IS FELT, ACTUATORDAMAGE MAY RESULT.


19/131



AIR CONDITIONING - FLOW CONTROL AND SHUTOFF VALVE


20/131



AIR CONDITIONING - LOW LIMIT CONTROL VALVE

Purpose

The pack low limit control valve (LLCV) does these functions:

Supplies hot air to remove ice from the condenser and from the outlet ofthe ACM turbine in all operating modes

Bypasses hot air around the ACM to prevent a compressor overheat whenthe pack operates in the AUTO mode

Controls the temperature of the air that flows from the pack to the maindistribution manifold when the pack operates in the STBY N mode

Location

The LLCV is part of the air cooling pack. The valve is in a section of duct that isaft and to the left of the condenser. It is difficult to see the valve from thebottom of the pack.


The LLCV is a spring-loaded closed, pneumatically operated valve. These arethe parts of the valve:

Position indicator Actuator Valve body Valve disk (not shown)

Shaft Pressure regulator (internal) (not shown) High and low pressure servos (internal) (not shown) High and low pressure servo adjustments Electromechanical control valve

The valve has pressure sense lines that connect to other components in thepack. Regulators in the valve use the pressure information to control theamount that the valve opens. These are the pressure sense line connections:

Turbine muff - supplies turbine outlet pressure data (low pressure) Pack outlet - supplies pack outlet pressure data (low pressure) Condenser inlet - supplies condenser inlet pressure data (high pressure)

Condenser outlet - supplies condenser outlet pressure data (highpressure)


21/131



AIR CONDITIONING - LOW LIMIT CONTROL VAL VE


22/131



AIR CONDITIONING - TEMPERATURE CONTROL VALVE

Purpose

The pack temperature control valve (TCV) controls the amount of hot air that

bypasses the air cycle machine (ACM). The valve does this to control thetemperature of the air that flows from the pack to the main distribution manifold.

Location

The TCV is part of the air cooling pack. The valve is in a section of duct on thelower side of the pack, forward of the primary heat exchanger.


The TCV is a 115v ac, single-phase, motor-controlled, disk type of valve. Thevalve weighs 3.7 pounds (1.4 kg). These are the main parts of the valve:

Electromechanical actuator Valve body Position transducer

An internal shaft connects the main parts of the TCV. The electromechanicalactuator sets the position of the valve and gives valve position information. Theactuator has these parts:

Position indicator Motor

Manual override knob Electrical connector

The valve body has these parts:

Inlet and outlet duct connections Arrow to show air flow direction Disk

The transducer gives valve position to the control and indication circuity. Theposition transducer has a housing and an electrical connector.

Functional Description

The electromechanical actuator moves an internal shaft (not shown). The shaftmakes these components move:

Position indicator Disk Position transducer

When the disk opens, it lets hot air bypass the ACM.

Interface

The TCV receives control signals from the pack temperature controller in the AUTO mode.

The TCV receives control signals from the backup temperature control card for

these functions:

STBY N STBY W


23/131



AIR CONDITIONING - TEMPERATURE CONTROL VALVE


24/131



AIR CONDITIONING - RAM AIR

General

The ram air door system is a variable-area duct system which supplies cooling

airflow through the heat exchangers. The air is used to cool pack air in theheat exchangers. The pack temperature controller controls the position of thedoors to control the pack outlet temperature.

Location

The ram air system is on the left side of each cooling pack. Access to thecomponents is through the pack bay access doors. The ram air inlet is flushwith the underside of the fuselage forward of the pack bay access door. Theexhaust door is on the underside of the fuselage forward of the main wheel well.

Operation

Airflow through the system is induced by forward motion of the airplane duringflight or by the ACM fan when on the ground with the airplane not moving ormoving slowly. The ACM fan turns anytime the pack operates. The air flowsthrough these components:

Variable inlet Honeycomb and fiberglass ducting Two heat exchangers Overboard through a variable exhaust opening Exhaust plenum/diffuser assembly

Indication

Ram air inlet and exhaust door positions show on the ECS/MSG page.

Actuator

The actuator controls the position of the ram air door. It receives control signalsfrom the pack temperature controller or the backup temperature control card.

Location

One actuator is near each inlet and exit door. The inlet door actuator is outsidethe inlet duct and to the right of the inlet doors. The exit door actuator is outsidethe left side of the ram air exit duct. Go through the large ECS access doors toget access to these actuators.


25/131



FLOW

FWD

FLOW

FWD

RAM AIR INLET DOOR RAM AIR EXIT DOOR

193193PRECOOL OUTPRIM HX IN 173171

DUCT PRESS

RAM IN DOOR TEMP VALVE

RAM OUT DOOR

42

0.710.80

0.72

40

0.610.620.75

BULK CARGO TEMP25

DIMK D TLF TFADWF AUX MIDAUX FWD

280.80

280.80

280.80

170.00

170.000.75

ECS/MSG

L PACK BITER PACK BITE

AUX TEMP BITE

30DUCT TEMP TRIM VALVE

ZONE TEMP BITEL

PRIM HX OUTCOMPR OUTSEC HX OUT TURB INPACK OUT

R

CARGO ZONE OVHTFWD CARGO FANBULK CARGO HEATAFT CARGO HEATFWD CARGO HEATHI FLOW INHIBIT

46 96 3 10 3

44 98 1 9 2

ECS MESSAGE PAGE

ACTUATOR(INBOARD)

INLET DOORFWD SECTION

INLET DOORAFT SECTION

HINGE

ACTUATOR(OUTBOARD)

EXIT DOOR

FWD

AIR CONDITIONING - RAM AIR


26/131



AIR CONDITIONING - HEAT EXCHANGERS

Purpose

The heat exchangers remove heat from the initial bleed air that goes into the

cooling pack and from the air cycle machines compressor output. Ambienttemperature ram airflow is the heat sink during this process. The plenumdirects ram air that leaves the primary heat exchanger into the air cycle machinefan inlet and to the ducting leading to the ram air exhaust opening.

Description

These are the primary and secondary heat exchangers features:

All aluminum Plate fin Single-pass crossflow Air-to-air heat exchangers.

On the cooling air plate, the fin has a wavy configuration with respect to the ramairflow. This increases heat transfer efficiency and reduces contamination. Usethe access panels underneath the heat exchangers to clean and inspect.

The primary and secondary heat exchangers are not the same. The secondaryheat exchanger has a wider ram air flow section and has stronger fins in the ramair inlet to protect against ingested hail. The primary exchanger weighs 40 lbs(18 kg) and the secondary exchanger weighs 54 lbs (25 kg).

The output side of the primary exchanger enters the fan air plenum and diffuser.This component is made of fiberglass, has a removable panel to get access tothe rear face of the primary heat exchanger for inspection, and weighs 15pounds (7 kilograms).

Operation

The primary heat exchanger cools hot bleed air as it goes into the cooling packon its way to the compressor section of the air cycle machine. The heat sink isambient air which is forced through the heat exchanger by ram air pressurewhen the airplane is moving. When the airplane is not moving, air is drawnthrough by a fan in the fan air plenum. The fan is on the same shaft as thecompressor and turbine. In a similar manner, hot compressed air from the

compressor section of the air cycle machine is cooled by the secondary heatexchanger on the way to the reheater.


27/131



AIR CONDITIONING - HEAT EXCHANGERS


28/131



AIR CONDITIONING - AIR CYCLE MACHINE

General

The air cycle machine (ACM) has these functions:

Increases air pressure in the compressor stage for the high pressure waterextraction part of the pack

Decreases air temperature in the turbine stage for pack outlet temperaturecontrol

Moves ambient air in the ram air system

For more information about the ram air system see the ram air system section.

Location

The ACM is part of the air conditioning pack. The ACM is on the right side of thepack near the center of the ECS bay.


The ACM has these high-speed rotating parts that connect to one shaft:

Turbine Compressor Fan

Air bearings support the shaft. The air bearings let the shaft rotate at high

speed with little friction. A tube connects the air bearings to each other. The ACM has a housing that has these connections:

Plenum/diffuser assembly connection Compressor inlet and outlet connections Turbine inlet, outlet, and bypass air connections Anti-ice hot air inlet and outlet connections Pressure sense line connection for the low limit control valve (LLCV)

The ACM weighs 42 pounds (16 kg).


Air that moves through the turbine becomes cool by rapid expansion. The airmakes the turbine turn. The faster the turbine turns, the colder it makes the air that comes out of the turbine. The speed that the turbine turns relates to theamount of air that moves through it. The more air that moves through theturbine, the faster it turns and the more cooling it supplies. The turbine makesthese components turn:

Shaft Compressor Fan

The compressor increases the pressure and the temperature of the air thatmoves through it. This increases the temperature differential in the secondaryheat exchanger to improve heat transfer. The high air pressure makes thewater separation part of the pack more efficient.The fan moves air through the

ram air system. It pulls air in from the ram air inlet through the heat exchangers.It pushes air out through the ram air exhaust. This lets a large amount ofambient air move through the heat exchangers when there is a small amount orno ram air.

Training Information Point

You can damage the air bearings if you turn the shaft in the wrong direction.The air bearings are self-acting and no external source of pressurized air isnecessary. Air from the turbine inlet supplies the pressure for the bearings.


29/131

TRAINING MANUALFOR TRAINING PURPOSES ONLYB767-3S2F ATA 21-50 Page - 29 4/25/13 EFF - ALL

AIR CONDITIONING - AIR CYCLE MACHINE


30/131



AIR CONDITIONING - WATER EXTRACTOR

Purpose

The water separation components remove moisture from he air that movesthrough the air conditioning pack.

Location

The water separation components are part of the air conditioning pack. Theseare the water separation components:

Primary water extractor Split duct (secondary) water extractor

The primary water extractor is part of the duct that connects the condenser tothe reheater. The split duct (secondary) water extractor is part of the duct that

connects the outlet of the secondary heat exchanger to the reheater.


Water changes from a vapor to a liquid on the walls of the duct between thesecondary heat exchanger and the reheater. The split duct water extractorcollects the liquid and lets it move to the sump of the water extractor. A drainline connects the split duct water extractor to the sump of the water extractor.

Air pressure makes the water move from the secondary extractor to the primarywater extractor.

When air moves through the extractor, swirl vanes cause the air to turn. As theair turns, the water in the air moves out to the duct wall. The water movesthrough the outer shell into the sump.

Air pressure pushes water from the sump drain to the water spray nozzle (notshown). A tube connects the sump drain to the nozzle.

The air/sump overflow has two connections. One connects to a tube and theother connects to a 90 degree fitting. The tube supplies air to the water spraynozzle. The air helps to atomize the water. The 90 degree fitting is open andhas no restrictions. When the sump is full, air pressure pushes water into theECS bay area through the fitting.


31/131


AIR CONDITIONING - WATER EXTRACTOR


32/131



AIR CONDITIONING - WATER SPRAY NOZZLE

General

A water spray nozzle on the ram air inlet duct sprays water extracted from

cooling pack supply air into the ram air inlet. The primary water extractorremoves water from the cooling pack supply air and adds it to the waterextracted by the secondary water extractor. A drain line from the primary waterextractor to the nozzle sends the water to the inlet plenum. A second line fromthe water extractor brings pressurized air to the water spray from the nozzle asit goes into the cooling ram air. The mist evaporates and cools the ram air. Thisincreases the efficiency of the ram air system.

Location

The water spray nozzle is in the ram air duct upstream of the secondary heatexchanger where the inlet duct turns inward.


If the water spray nozzle becomes clogged, an overflow line on the primarywater extractor lets water flow onto the inside of the ECS bay access door.


33/131


AIR CONDITIONING - WATER SPRAY NOZZLE


34/131



AIR CONDITIONING - REHEATER

Purpose

The pack reheater has these functions:

Operates with the condenser to remove heat from the air in the pack beforeit flows through the water extractor; this lets the moisture in the air collect inthe water extractor

Adds heat to the pack air to add energy to the air; the heated air helpsoperate the turbine in the air cycle machine

Location

The pack reheater is part of the air cooling pack. The reheater is in the forwardleft section of the pack.


The pack reheater is an air-to-air, plate-fin, crossflow type heat exchanger. Twoisolated airstreams flow through thin-walled channels. The channel walls aremade of plates and fins to increase the surface area. The reheater hasconnections to these components:

Secondary heat exchanger outlet Condenser inlet Water extractor outlet ACM turbine inlet

The pack reheater weighs 10 pounds (3.7 kg).


The pack reheater removes heat from the air that flows from the secondary heatexchanger to the condenser. The pack reheater also adds heat to the air thatflows from the water extractor to the ACM turbine.


35/131


AIR CONDITIONING - REHEATER

B767 3S2F ATA 21 50


36/131



AIR CONDITIONING - CONDENSER

Purpose

The condenser operates with the reheater to decrease the temperature of the

air in the pack before it flows through the water extractor. This lets the moisturein the air collect in the water extractor.


The condenser is an air-to-air, plate-fin, cross-flow type of heat exchanger. Twoisolated airstreams flow through thin-walled channels in the core. The channelwalls are made of plates and fins to increase the surface area. The core alsohas one section that lets air bypass the usual channels. This is the cold air bypass section. The condenser has connections that connect to thesecomponents:

Reheater outlet Water extractor inlet ACM turbine outlet Main distribution manifold (pack outlet duct) Upstream high pressure sense - lets the low limit control valve (LLCV)

monitor for ice Downstream high pressure sense - lets the LLCV monitor for ice ACM compressor outlet - hot air for anti-ice

The condenser weighs 14 pounds (5.2 kg)


These are the two isolated airstreams that flow through the condenser:

High pressure air from the reheater Low pressure air from the turbine section of the ACM

The condenser decreases the temperature of the high pressure air that flowsfrom the pack reheater to the water extractor. The air temperature decreasesby low pressure air that flows from the ACM turbine to the main distributionmanifold. The high pressure air temperature decreases to a low value so thatany moisture in the air changes from a vapor to a liquid. The moisture and thecool high pressure air flows to the water extractor.

A small amount of hot air goes to the condenser so ice does not collect in thecondenser. The condenser has anti-ice passages on one side of the plate-fincore. Hot air from the outlet of the ACM compressor flows through thesepassages. A tube connects the passages to the compressor outlet.

The cold (low pressure) air that flows from the ACM turbine to the maindistribution manifold, flows through the condenser two ways. Some of the airflows through the plate-fin core, and some flows through the bypass. Thebypass prevents the ACM from a stall if ice causes a blockage of the plate-fincore.


37/131


AIR CONDITIONING - CONDENSER

B767 3S2F ATA 21 50


38/131



AIR CONDITIONING - SENSORS AND SWITCHES

Pack Outlet Temperature Bulb

The pack outlet temperature bulb is located in the pack outlet duct between thecondenser and the cabin air supply check valve. It provides a signal to EICASfor a temperature display on the ECS/MSG page.

Pack Overheat Switch

The pack overheat switch is used to sense pack discharge temperature at thecondenser outlet. It is located in the pack outlet duct. It actuates at 190of (88c)and resets at 160f (71c). It provides a signal to the flow control card to drive thepack to full cold (ram doors open and temperature control valve closed) andilluminates an inop light on the P5 panel, requiring reset.

Pack Temperature Sensor

The 2 pack temperature sensors are single isotherm pair thermistors whoseresistance varies inversely with temperature. Both are located in the waterextractor outlet. One ("AUTO") provides a temperature signal to the packtemperature controller for feedback information. With this signal the controlleralso limits the temperature to 145deg.f maximum and 35deg.f minimum 0deg.fminimum above 31,000 ft for pack output.

The standby sensor provides a resistive signal of 40deg.f to the pack standbycontroller which in turn controls the pack discharge temperature by modulatingthe low-limit control valve in the stby-n mode.

Compressor Outlet Overheat Switch

The compressor outlet overheat switch functions as a thermal protective deviceand is located in the compressor outlet duct. The switch is snap acting andactuates at 490f. When activated, it provides a signal to the flow control card toclose the flow control valve and open the ram air doors and temperature controlvalve and illuminate both the inop and pack off lights on the P5 panel.

Compressor Outlet Temperature Sensor

The 2 compressor outlet sensors are single isotherm pair thermistors located inthe compressor outlet duct. One provides a resistive signal to the pack

controller to limit compressor discharge temperature. At 400deg.f the ramdoors are positioned full open. At 425deg.f the controller provides a signal tothrottle the flow control valve during high flow mode operation. At 450deg.f thecontroller provides a signal to the logic card to close the flow control valve (packtrip). The Standby sensor provides a signal to the pack standby controllerwhich in turn limits the compressor discharge temperature to 450deg.f duringStby-N operation.

Altitude Switch

The altitude switch consists of a pressure-sensing aneroid capsule controllingan electrical switch. It is located in the left pack on the keel beam adjacent tothe trim air modulating valves. It provides an altitude signal to the packcontrollers for minimum pack output temperature limiting. During climb,switching occurs between 29,500 and 32,500 feet which provides a 0 deg. oflimit for pack discharge. during descent switching occurs at some altitudeabove 28,000 feet which provides a 35 deg. of limit for pack discharge at lower

altitudes.


39/131


AIR CONDITIONING - SENSORS AND SWITCHES

ALTITUDEWITCH

ALTITUDEWITCHLEFT ECS

AY

TRAINING MANUALB767 3S2F ATA 21 50


40/131



AIR CONDITIONING - CABIN AIR SUPPLY CHECK VALVE

Purpose

The cabin air supply check valve prevents the flow of air from the maindistribution manifold into the air cooling pack.

Location

The check valve is in the forward, inboard section of the ECS bay. The valve isadjacent to the keel beam and pressure bulkhead.


The cabin air supply check valve has one flapper. The air supply check valvehas these parts:

Flapper Valve body Hinge pin Flapper stop Connection for the pack LLCV


The flapper hinges around the hinge pin. The flapper stop limits the flapperopen position. When the pressure upstream of the cabin air supply check valveis more than the pressure downstream, the valve opens.

Interface

The pack outlet sense line for the LLCV connects to the cabin air supply checkvalve. For more information about the LLCV, see the pack low limit controlvalve pages in this section.


41/131

TRAINING MANUALB767-3S2F ATA 21-50


42/131


B767 3S2F ATA 21 50 Page - 42 4/25/13 EFF - ALL

AIR CONDITIONING - PACK CONTROL COMPONENTS

Pack Temperature Controller

The pack temperature controller is a micro-computer that controls thepositioning of the ram air system and temperature control valve in AUTOmode. It is located in the E3 -1 rack. It contains BITE to monitor and storeLRU (line replaceable unit) faults for the previous ten flights.

Pack Standby Controller

The pack standby controller is an analog controller that controls the low limitcontrol valve in the "Stby-N" mode.

Flow Control Card

The flow control card provides logic for the pack flow control valve in the normal

and high flow modes and for compressor outlet and pack overheat signals. Itcontrols the "INOP" and "PACK OFF" lights and respective EICAS messages.

Back-Up Temperature Control Card

Located in the P50 card file, the back-up temperature control card provideslogic for standby control of the cooling pack. It provides positioning of the ramair door actuators and the temperature control valve for standby operation, packshut-down and pack/compressor overheat.

The back-up temperature control card also supplies the back-up temperature

command signal (75deg.f) to its respective pack with a failure of a forward or aftcabin zone temperature control system.

Left Pack Flow and Cargo A/C Controller

The left pack flow and cargo A/C controller (PFCAC) controls the forward cargo A/C through these components:

Cargo A/C shutoff valve Forward cargo heat shutoff valve Cargo exhaust valve Cargo ground exhaust valve Cargo ground exhaust backup valve

High flow command to the left pack.


43/131


AIR CONDITIONING - PACK CONTROL COMPONENTS

E1-5 RACK

TRAINING MANUALB767-3S2F ATA 21-60


44/131


B767 3S2F ATA 21 60 Page - 44 4/25/13 EFF - ALL

TEMPERATURE CONTROL - GENERAL DESCRIPTION

General Description

The primary zone temperature controller (ZTC) controls the trim air temperaturecomponents. The ZTC controls these components to get the necessarytemperatures in the cabin zones and flight deck. The controls are on the P5 airconditioning panel in the flight deck.

The source of the trim air for the forward cargo compartment comes from thepneumatic distribution system through the cargo heat shutoff valve. The valveis controlled by the pack flow cargo air conditioning controller (PFCAC). ThePFCAC opens the cargo heating shutoff valve if both packs are operating, thereare no inhibits, and the control switch on the P5 panel is in the AUTO position.The aux zone controller monitors the forward cargo compartment zone and ductsensors and the demand signal from the ZTC. The aux zone controller controlsthe left pack temperature controller to the largest demand of either the forward

cargo compartment or the cabin.

The trim air pressure regulation and shutoff valve controls the trim air supplypressure to a set value. The trim air pressure sensor gives trim air ductpressure information to the ZTC. The ZTC uses it for control and indication.


45/131


FWD CARGO AIR COND

INOP

FAULT C

AUTO

OFF W

CARGO HEATFWD AFT BULK

ON ON ON

OVHT OVHT OVHT

BITEINSTRUCTIONS GO CONTROLLER

PR ESSTEST

FAULT

SYSTEM CONTROLSWITCH

COMPT TEMP

INOP INOP INOP

PACK MIXMANF ZONE COMPRESSORSENSOR SENSOR SENSOR VALVE

ALTITUDE TEMP CONT SWIT CH VALVE

RAM RAM FLOW LOWI NL E T O U TL E T C O NT L I MI T ACTR ACTR VALVE VALVE

FAULTS

PREVIOUSTEMP CONTROLC W

FLT DECK FWD CAB AFT CAB AUTO AUTO AUTO

BIT FLIGHTS VERIFY RESET

AIR CONDITIONINGCONTROL PANEL(PILOT'S OVERHEAD

C MAN W C W C WMAN MAN

LEFT AUTO PACKTEMP CONTROLLER

PANEL P5) TRIM AIRON

OFF

INOPPACKOFF

AUTOOFF

L RPACK PACK

RESET RESET

N OFF

INOPPACKOFF

AUTON

TRIM AIR PRESSUREREGULATING VALVE

ST STB B

W Y W Y TRIM AIRMODULATING

VALVE

ZONE TEMPERATURESENSOR

PACK FLOW CARGODUCT AIR ZONE TEMP FORWARD CARGO AIR AIR CONDITIONING AUX ZONE TEMP

TEMP SENSOR CONTROLLER CONDITIONING SHUTOFF VALVE CONTROLLER (PFCAC) CONTROLLER


B767-3S2F ATA 21-60 TRAINING MANUAL

Page - 45 3/19/13 EFF - ALL FOR TRAINING PURPOSES ONLY

65 70 70

With the Pack SelectSwitch in Auto, Pack TempOutput should be based onlowest temp selected

When Trim Air PRSOVcloses all three inoplights illuminate on

temp panel

Page 45


TRAINING MANUAL B767-3S2F ATA 21-60


46/131

TRAINING MANUALFOR TRAINING PURPOSES ONLY Page - 46 4/25/13 EFF - ALL

TEMPERATURE CONTROL - ZONE TEMPERATURE CON-TROLLERS

Purpose

The primary and auxiliary zone temperature controllers (ZTC) control thetemperature in these areas:

Cargo compartment Forward cargo air conditioning Flight compartment

The pack flow cargo air conditioning controller (PFCAC) controls the cargo heatshutoff valve.

Location

The zone temperature controller and the auxiliary zone temperature controllerare in the main equipment center. The zone temperature controller is on theE3-1 shelf. The auxiliary zone temperature controller is on the E1-5 shelf.


The primary zone temperature controller and the auxiliary zone temperaturecontroller have BITE.

Interface

The zone temperature controller (ZTC) receives and sends signals to thesecomponents:

Trim air PRSOV Zone temperature sensors Trim air modulating valves Duct sensors

The aux temperature controller receives and sendssignals to this zone:

Forward cargo zone


47/131


MAIN EQUIPMENT CENTER

(E1-5)PFCAC

PRIMARY ZONE TEMP CONTROLLER AUXILIARY ZONE TEMP CONTROLLER

(LOOKING FORWARD)E3 RACK

BITE INSTRUCTIONS PRESS TEST

TRIMVALVE

DUCTSENSOR

ZONESENSORSELECTOR

FWDAUX

OGRACOGRAC

FWDAUX

MIDAUX

MIDAUX

FAULTS

AUX

GO CONTROLLERFAULT

VER IFY RES ETPREVIOUSFLIGHTSBIT

FWD

BITE INSTRUCTIONS PRESS TEST

TRIMVALVE

DUCTSENSOR

ZONESENSORSELECTOR

FWDZONE

FLIGHT

MIDZONE

FAULTS

GO CONTROLLERFAULT

VE RI FY R ES ETPREVIOUSFLIGHTSBIT

DECK

AFTZONE

FWDZONE

FLIGHT

MIDZONE

DECK

AFTZONE

TEMPERATURE CONTROL - ZONE TEMPERATURE CONTROLLERS



48/131

FOR TRAINING PURPOSES ONLY Page - 48 4/25/13 EFF - ALL

TEMPERATURE CONTROL - TEMP PRSOV

Purpose

The trim air pressure regulating and shutoff valve (PRSOV) controls and shutsoff trim air.

General

The trim air PRSOV controls the trim air supply pressure from 3 to 5 psi abovecabin pressure. The trim air switch enables the trim air operation when it is setto ON. The switch turns off the trim system when in the OFF position. TheEICAS advisory message TRIM AIR shows when the switch is OFF.

LocationThe trim air PRSOV is in the left ECS bay adjacent to the keel beam. Open theleft ECS access door to get access to the valve.


The trim air PRSOV has a manual override to lock the valve closed for dispatchrelief.


49/131


TEMPERATURE CONTROL - TEMP PRSOV



50/131


TEMPERATURE CONTROL - TRIM AIR MODULATING VALVE

Purpose

The trim air modulating valves add bleed air to each zone to control thetemperature of their zones.

Location

There are three valves in the forward part of the left ECS bay adjacent to thekeel beam.


Each valve has these parts: Electric actuator Valve body

Manual override knob Variable resistor Electrical connector

All of the trim air modulating valves are the same. Each has an internal disc inthe valve body. The electrical actuator has these internal parts:

Motor Position indicator Gears

The motor controls the disc position. The position indicator shows the discposition.


A close or open signal from the ZTC operates the valves. Aux ZTC operates theforward cargo air conditioning trim air modulating valve.


The trim air modulating valve has a manual override for dispatch relief.


51/131


TEMPERATURE CONTROL - TRIM AIR MODULATING VALVE



52/131


TEMPERATURE CONTROL - DUCT AND ZONE TEMP SEN-SORS, TEMP BULBS AND OVERHEAT SWITCHES

Purpose

The zone temperature sensors provide temperature data of their zone to thezone temperature controllers. The zone temperature bulbs supply temperaturedata that shows on the temperature indication module above the A/C controlpanel.


The sensors are dual element thermistors with an electrical connector. All of thezone temperature sensors are interchangeable. The bulbs are a single elementthermistors. Each bulb has an electrical connection.

Zone Temp Sensor Location

The sensors are in an air plenum that connects to a fan located in the affectedzone. In the flight compartment, the sensor is in the ceiling to the left of the P-11circuit breaker panel. The sensors in the main deck cargo compartment are inthe overhead ducting which is connected to the fan for that zone.

Duct Zone Temp Sensor Location

The flight compartment sensor is in the duct in the left outboard side of the mainequipment center. The cargo zone duct temperature sensors are in theoverhead distribution ducts where the risers connect to the distribution duct.

Functional Description of the Sensors

The duct zone sensor supplies a temperature signal of the duct to the zonetemperature controller. The controller compares this data with the cabintemperature selector and zone temperature sensor.

Purpose of the Overheat Switches

The zone duct overheat switch provides protection for the air conditioningdistribution system.


The switch has a probe body, electrical connector, and flange. A bimetalelement that is normally open is in the duct overheat switch.

Location

The flight compartment duct overheat switch is in the duct in the left outboardside of the main equipment center.

The cargo duct overheat switches for each cargo zone are in the supply ductswhere the distribution duct and risers interface.


If the temperature in the supply duct is 190F (83C), the switch closes. After theswitch closes, the related INOP light comes on and the related zone trim air

modulating valve closes.


53/131


TEMPERATURE CONTROL - ZONE TEMP SENSOR AND BULB



54/131


TEMPERATURE CONTROL - FWD CA RGO ZONE / DUCT AIRTEMP SENSORS, OVHT SWITCH AND TEMP BULB

Purpose

The duct air temperature sensor gives temperature data of the cargocompartment supply duct to the auxiliary zone temperature controller. The zoneduct overheat switch gives protection for the air conditioning distribution system.

The zone duct overheat switch gives protection for the air conditioningdistribution system.

Location

The forward cargo air conditioning zone duct temperature sensor and overheatswitch are in the forward cargo duct.


The sensor supplies a temperature signal of the duct to the auxiliary zonetemperature controller. If the temperature in the supply duct is 190F, theoverheat switch closes. After the switch closes, the related INOP light comeson, and the related zone trim air modulating valve closes.

Zone Temp Sensor/Overheat Switch and Temp Bulb Location

The temperature bulb and temperature sensor are in the temperature sensingassembly on the left forward cargo compartment sidewall. The cargo overheat

switch is connected to the system fan ventilation system on side of the panel.


The forward cargo compartment temperature bulb gives a signal to EICAS.EICAS shows the forward cargo temperature on the STATUS page. Theforward cargo compartment sidewall overheat switch sends a signal to thePFCAC card which signals the AUX ZTC to shut off the heat.


55/131


TEMPERATURE CONTROL - FWD CARGO ZONE / DUCT AIR TEMP SENSORS, OVHT SWITCH AND TEMP BULB

TRAINING MANUAL B767-3S2F ATA 21-40P 56 4/25/13 EFF ALL


56/131


AIR CONDITIONING - MAIN AIR DISTRIBUTION

Main Distribution Manifold

The main distribution manifold is a mix manifold with ducts and a ground airservice connector. The manifold also removes water from the airflow to givesome humidity control.

Mix Manifold

The mix manifold is forward of the forward cargo compartment aft pressurebulkhead.

Air goes in the mix manifold from one or the two inlet ducts. This airflow causesa centrifugal flow in the manifold. The swirl devices in this flow makes aturbulence. The turbulence removes water from the air and lets the watercollect on the manifolds inner wall.

The air continues up the manifold in a spiral to a point near the water ring. Thering makes more turbulence and removes remaining water in the airflow. Theair goes through the water ring and into the flow straightener. The straightenerstops the swirl movement of the air and gives a constant pressure and volumedistribution to each outlet duct.

The water removed at the swirl devices and the water ring flows down themanifolds on the inner wall. The water collects at the bottom and goes outthrough the water drain tube and through a drain port.

Ground Air Service Connector

The ground air service connector permits input of conditioned air from a groundair cart into the airplane distribution system. The connector is an eight-inchdiameter receptacle with an internal swing check valve. The swing check valveis spring-loaded to close.

The connector is on the bottom of the fuselage immediately forward of the leftair conditioning pack.


57/131


AIR CONDITIONING - MAIN AIR DISTRIBUTION


B767-3S2F ATA 21-40 P ge 58 4/25/13 EFF ALL


58/131

FOR TRAINING PURPOSES ONLYPage - 58 4/25/13 EFF - ALL

AIR CONDITIONING - FLIGHT COMPARTMENT AIR DISTRIBU-TION

Purpose

The flight deck conditioned air distribution system moves air from the mixmanifold to the flight compartment. Distribution ducts connect from the mixmanifold along the left side of the airplane to the flight compartment.


Conditioned air from the mix manifold flows to the flight compartment throughdedicated ducts. Floor outlets give the air to different parts of the compartment.Gasper outlets give conditioned air to each crew station, and an overhead outletgives air to the full compartment. The windshield diffusers give conditioned airto the full window area to prevent window fogging.

Floor Outlets/Overhead Outlet

The flight compartment floor perimeter has twelve floor outlets. The floor outletis a housing that has these components:

- Air grille- Flow straightener - Distributor (in some).

The overhead outlet is a plenum around an acoustic baffle and a nozzle. Thebaffle decreases the airflow through the nozzle to prevent too much noise. The

nozzle gives airflow in four different directions in the flight compartment.

Windshield Diffuser

The overhead drip shield has the forward windshield diffusers. The diffusersinclude an airflow straightener and a baffle plate to make sure of equaldistribution of air over the windshield.

Gaspers

The flight compartment has five adjustable gaspers, two on the outboard side ofthe captain station and two on the outboard side of the first officer station. The

fifth gasper is forward and above the entrance to the flight compartment. Allgaspers are a drilled ball in a socket and an adjustable valve to control airflowvolume.


59/131


AIR CONDITIONING - FLIGHT COMPARTMENT AIR DISTRIBUTION


B767-3S2F ATA 21-40 Page 60 4/25/13 EFF ALL


60/131

FOR TRAINING PURPOSES ONLYPage - 60 4/25/13 EFF - ALL

AIR CONDITIONING - BULK CA RGO VENT COMPONENTS

Component location

These are the bulk cargo ventilation system components:

Fan and check valve above the ceiling of the bulk cargo compartment Bulk cargo fan relays in the P37 panel in the main equipment center Bulk cargo heat control switch on the P5 panel and vent fan selector

switch on the P61 panel

Interfaces

These components have an interface with the bulk cargo ventilation system:

Aft cargo fire switches on the P8 panel Fuel jettison switch on the P5 pane


61/131


AIR CONDITIONING - BULK CARGO VENT COMPONENTS

FIRE DETECTIONCONTROL PANEL (P8)

1

DISCH

FWD

MAIN

AFT DISCHDEPR/

ARM

ARM

CARGO FIRE

DISCH

DEPR

FWD

ARMED

ARMED

AFT

ARMED

MAIN

FUEL JETTISON CONTROL PANEL

VENTNORM

BULK CARGO HEAT

SELECTORVENT FAN MODEBULK CARGO

SWITCH

BULK CARGOHEAT CONTROL

OVHT

ON

AFT BULK CARGO HEAT

CHECK VALVEVENT FAN ANDBULK CARGO

BULK CARGO COMPARTMENT(LOOKING AFT)

DOOR (REF)BULK CARGO

BULK CARGORELAY FAN

INLET WIRE

ASSEMBLYCHECK VALVEFAN AND

SCREEN

ELECTRICALCONNECTOR

DUCTFLEXIBLECLAMP

FANBULK CARGO

BULK CARGO VENTILATION FAN AND CHECK VALVE

P37

CARGO HEAT CONTROL

INBD

FWD

OUTBD

LOUVERAIR OUTLET

(P5)

(P5)

(P61)

JETTISONFUEL

L-NOZZLE-ROFF

ON

VALVE

ON ON

VALVE

25 OR 30WITH FLAPDO NOT JETT

FAULT




62/131

FOR TRAINING PURPOSES ONLYPage 62 4/25/13 EFF ALL

AIR CONDITIONING - FWD CARGO VENT

Purpose

The forward cargo compartment ventilation system removes odors from thecompartment and vents them overboard.

General

The forward cargo ventilation system has a forward cargo exhaust valve.Relays give control for the forward cargo exhaust valve. The pack flow and cargo air conditioning controller (PFCAC) monitor allcomponents and supply signals to EICAS if the system has any faults. In theair, the forward cargo exhaust valve is open. It lets air out of the compartment.

Interfaces

The forward cargo ventilation system interfaces with these systems:

EICAS Forward and aft cargo fire extinguishing systems Equipment cooling system Air ground system Air cooling pack system

For more information about the systems that interface with the forward cargoventilation system, see the FWD CARGO VENT INTERFACE page in thissection.

Operation

The pack flow and cargo A/C controller causes the forward cargo exhaust valveto open when these conditions exist:

The airplane is in the air The FWD CARGO AIR COND selector, on the P5 panel, is on The FWD, AFT, AND MAIN CARGO FIRE switchlights, on the P8 panel,

are not armed The EQUIP COOLING selector, on P5 panel, is in AUTO or STBY

The L and R PACK switchlights, on the P5 panel, are not OFF or INOP


63/131



AIR CONDITIONING - FWD CARGO VENT




64/131

FOR TRAINING PURPOSES ONLYg

AIR CONDITIONING - LAV/GALLEY DUCT VENTILATION

Purpose

The ventilation system draws smoke and odor-filled air from the lavatory andgalley during the flight through overhead ducting and exhausts it overboardthrough a venturi assembly on the right side of the flight deck.

General Description

The lavatory and galley ventilation system has the following components:

Galley ventilation filter Restrictors Muffler assembly Venturi assembly.


65/131



AIR CONDITIONING - LAV/GALLEY DUCT VENTILATION




66/131

g

AIR CONDITIONING - HEATING INTRODUCTION

Purpose

Heat sources add heat to flight deck, cabin areas, and cargo compartments tokeep temperatures at necessary levels.

Forward Cargo Heating

The forward cargo compartment uses air from the pneumatic system to keeptemperature in limits.

Aft and Bulk Cargo Heating

The aft and bulk cargo compartments use air from the pneumatic system tokeep temperature in limits.

Supplemental Heating

These areas have electric heaters to keep temperature in limits:

Flight deck foot and shoulder heaters Door heaters


67/131



AIR CONDITIONING - HEATING INTRODUCTION




68/131

AIR CONDITIONING - FORWARD CARGO COMPARTMENTHEATING INTRODUCTION

Purpose

The heating system in the forward cargo compartment keeps the temperature ofthe compartment above freezing.

General Description

The forward cargo heating system interfaces with the airplane pneumaticsystem. The forward cargo heating system has these components:

Forward cargo heat shutoff valve Forward cargo heat control valve Temperature control switch Forward cargo sidewall temperature switch

Overheat switch

The heating shutoff valve in the forward car go compartment is controlled by thecargo heat switch. The switch is on the P5 overhead panel. The temperaturecontrol switch controls the valves in the forward cargo. The switch is below thecargo deck floor.

This switch controls the temperature in the forward cargo compartment. Itoperates when the air conditioning system is on for the forward cargocompartment.

The overheat switch closes the car go heat shutoff valve for the forward cargoarea. It does this if the temperature in the compartment is more than 90F.


69/131



AIR CONDITIONING - FORWARD CARGO COMPARTMENT HEATING INTRODUCTION




70/131

AIR CONDITIONING - FORWARD CARGO COMPARTMENTHEATING VALVES A ND TEMP SWITCHES

Purpose

The two forward cargo compartment heat valves control the hot pneumaticsystem air added as heat to this compartment. One valve is a shutoff valve, andthe other valve is a flow control valve.


The forward cargo compartment heat valves have theseparts:

Body and vane assembly Electrical actuator assembly

Location

The forward cargo heat shutoff heat valve is in the right ECS bay. The forwardcargo heat flow control valve is in the lower part of mix manifold bay.

Operation

When the forward cargo air conditioning is on, the temperature in the cargocompartment is set between 40F and 70F. When the cargo heating is on, thetemperature in the cargo compartment is set between 40F and 50F.

Inhibits

The operation of the valves is not enabled if any of these conditions occur:

Temperature in the forward compartment is more than 90F (32C) (floor orside wall) and the shutoff and temperature control valves are open

Cargo heat valve is OFF Forward cargo fire switch is armed Cargo air conditioning fault occurs


The electrical actuator assembly operates with single phase 115v ac, 400 Hz.You can operate the valve manually. To do this, you push on the actuatoroverride lever and move it to the open or close position. You can lock the valveassembly open or closed. To do this, you pull and turn the plunger assembly

knob. The valve cannot operate electrically or manually while locked.

General

Two temperature switches control the forward cargo compartment temperature.The switches are below the cargo floor in the middle of the compartment. Thecontrol switch operates from 40F to 50F. The overheat switch operates from80F to 90F.

Indication

These two messages show on the flight compartment displays in acompartment heat/overheat condition:

FWD CARGO OVHT (advisory) FWD CARGO HEAT (maintenance)

The FWD CARGO OVHT advisory level message shows when both theseconditions are present:

The temperature below the for ward cargo floor is more than 90F The flow valve for the cargo heat control does not close

The FWD CARGO HEAT maintenance level message shows whenthese conditions are present:

The two valves are open The cargo heat system is in normal operation


71/131



AIR CONDITIONING - FORWARD CARGO COMPARTMENT HEATING VALVES AND TEMP SWITCHES

FWD TEMP SWITCHES CONTROLWITCH

OVERHEATWITCH




72/131

AIR CONDITIONING - AFT / BULK CARGO COMPARTMENTHEATING

General

AFT and BULK cargo heat systems use air from the center part of thepneumatic distribution system to keep the compartments above freezing. Youput the aft and bulk cargo compartment heating systems ON or off with the

AFT and BULK cargo heat control switches.

Control Switch - Out Position

When a switch is set to the out position, the control circuit sets the system to off.The shutoff valve and the control valve are set to the close position.

Control Switch - In Position

When you push a switch in, the upper part of the switch shows an ON label, andthe control circuit sets the shutoff valve to open. The control circuit also letsthe control valve and a temperature switch operate together to keep thecompartment above freezing.

The aft cargo area has one temperature switch. The switch opens the controlvalve when the compartment temperature is 40F or less and closes the valvewhen the compartment temperature is 50F or more. The bulk cargo area has two temperature switches, norm and high. You selectwhich one the control circuit uses with the bulk cargo heat selector. When theselector is set to NORM, the control circuit uses the norm temperature switch.The switch opens the control valve when the compartment temperature is 40For less and closes the valve when the compartment temperature is 50F or more.When the selector is set to VENT position, the control circuit uses the hightemperature switch. The switch opens the control valve when the compartmenttemperature is 65F or less and closes the valve when the compartmenttemperature is 75F or more.

When the selector is set to VENT position, the control circuit uses the hightemperature switch. The switch opens the control valve when the compartmenttemperature is 65F or less and closes the valve when the compartmenttemperature is 75F or more.

A maintenance message shows when the control and the shutoff valves areopen at the same time.

Overheat Protection

Each compartment has an overheat switch. The switch operates with the

control circuit to set the shutoff valve to close when the compartmenttemperature is 90F or more.

An OVHT light and a caution message show when the control valve is open anda compartment temperature is 90F or more.

For usual operation, if the control valve is in the close position and thecompartment temperature is 90F or more, the OVHT light and the cautionmessage do not show.

Location

The flight compartment has the cargo heat control panel and the bulk cargomode selector. The aft cargo area has these components:

Aft and bulk shutoff valves Aft and bulk control valves Aft cargo heat duct Aft temperature and overheat switches

The bulk cargo area has these components:

Bulk temperature and overheat switches

Bulk temperature sensor Bulk Cargo Temp Bulb Bulk cargo heat duct

P5 PANEL P61 PANEL


73/131



WELLWHEEL AFT CARGO COMPARTMENT BULK CARGOCOMPARTMENT

BLEEDAIR

APU

BULK CARGO HEAT DUCTAFT CARGO HEAT DUCT(UNDER FLOOR)

CENTERPNEUMATICDISTRIBUTIONDUCT

(SIDEWALL/CEILING)

PLAN VIEW

AFT TEMP AND

BULK TEMP AND OVHT SWITCHES

FWD

OVHT SWITCHESCONTROL

ENGINEBLEEDAIR

VALVES

BULK TEMP SENSOR

AFT CARGO

BULK CARGODOOR (REF)

CARGO HEAT MODE SELECT

NORMVENT

OVHT

ON

OVHT

ON

OVHT

ON

AFT K LUBDWFCARGO HEAT

CONTROL PANEL

CARGO

SHUTOFFVALVES

(LEFT SIDEWALL AREA)(UNDER FLOOR)

(RIGHT SIDEWALL)FLIGHT COMPARTMENT

DOOR ( REF) NET/BARRIER

AIR CONDITIONING - AFT / BULK CARGO COMPARTMENT HEATING

BULK TEMP BULB




74/131

AIR CONDITIONING - CARGO COMPARTMENT HEATINGOPERATION

Cargo Heat Control

You use the switches on the cargo heat control panel to put the cargo heatingsystems on or off for these compartments:

Forward Aft Bulk

When a system is on, the usual target temperature for the related compartmentis 40F to 50F.

You use the bulk cargo heat selector to change the target temperature for thebulk cargo area and to put the bulk cargo ventilation system ON or off. The

NORM position sets the target temperature of 40F to 50F and puts off theventilation system. The VENT position sets the target temperature of 65F to75F and puts the ventilation system on. For more information about the bulkcargo ventilation, see the air conditioning ventilation system section.

Usual Indications

Bulk cargo temperature data shows on the STATUS display and on the ECS/MSG display. The ECS/MSG display also shows a related maintenancemessage when the two heating valves (shutoff and control) are open at thesame time. The messages let you know when a system supplies heat to acompartment.

Overheat Indications

An OVHT light in a switch and an advisory message show when the controlvalve for a compartment is open and the compartment temperature is more than90F. The indications go away or do not show if the control valve closes or if thetemperature is less than 80F.


75/131



BULK CARGO TEMP 21

ECS/MSG DISPLAY

BULK CARGO HEATAFT CARGO HEAT

STATUS DISPLAY

BULK CARGO TEMP 21

SHOWS WHEN SHUTOFF VALVE OPEN AND CONTROL VALVE OPEN4

4

SHOWS WHEN CONTROL VALVE OPEN AND COMPARTMENT TEMP => 90F (32C)1SETS THE BULK CARGO TARGET TEMP AT 40F TO 50F (4C TO 10C)2SETS THE BULK CARGO TARGET TEMP AT 65F TO 75F (18C TO 24C) AND3

FWD CARGO HEAT

PUTS ON THE BULK CARGO VENTILATION SYSTEM

NORMVENT

CARGO HEAT CONTROL PANEL (P5)

MODE SELECT PANEL (P61)

OVHT

ON

OVHT

ON

OVHT

ON

AFT K LUBDWFCARGO HEAT

BULK CARGO HEAT

1 11

2

3

AIR CONDITIONING - CARGO COMPARTMENT HEATING OPERATION

TRAINING MANUALFOR