WESTPOINT Commercial Air conditioners

INVERTER VRF COMMERCIAL A/C

Contents

What’s WMV & VRF?1

Residential central air AC2

WMV energy consumption analysis3

Digital scroll VS Inverter4

Part ⅠGMV & VRF

Review of VRF(VRV) Variable Refrigerant Flow

Developing from traditional split type air conditioner.

Consist of outdoor units, indoor units, Refnet, controller etc.

One outdoor unit can drive at least 16 indoor units, with which different capacity and appearance.

Applied intensively in office building, hotel, high grade department, villa etc.

Introduction of GMV

W– WESTPOINT

M – Multi-connected (Max. 1:32)

V – VRF system

2 ways to achieve VRV

InverterOriginating from Japan, frequency conversion;Electrical adjustment;

Digital scrollTechnology from Copeland; Mechanic adjustment;

Rotor

Reluctance motor

E.G. WMV in office building

Combination

with

Outdoor fresh

air processor

Part ⅡResidential central air conditioner

When central AC enter residential area…

Virtues of Central Air Conditioner Central air conditioner-centralized processing 、 distributing； Baring comparatively higher EER, more energy saving;

Residential Central Air Conditioner More comfortable, lower noise, less vibration, more accurate

adjustment;

Types of residential central AC Duct type Mini chiller WMV

Family of residential central AC

1. Duct type• Low initial investment;

• Indoor air quality improve by introduction of fresh air

• Require enough height to layout the duct;

• Individual adjustment for single room not available

Mini Chiller-Hydraulic system

•All-Water system (water or ethylene alcohol);

•Adopt Fan coils as terminals, space saving;

•Without fresh air introduction;

•Individual control for each room available;

2. Mini Chiller

E.G. WMV in detached house

3. WMV

• Energy-saving;

• Low initial investment;

• Comfortable & Accurate;

• Individual control;

Figure: Ratio of VRV application in Japan

Old building redecoration

New facility

Part Ⅲ WMV energy saving analysis

New orientation in working concept

Adopting digital scroll compressor

Using refrigerant as heat transfer medium

Sophisticated controlling network

Combination with heat recovery processor

Core factorsCore factorsSaving energySaving energyCore factorsCore factors

Saving energySaving energy

1. New orientation in designing concept

Traditional designing base on the most sever outdoor condition.

Peak of EER/COP sets at partial load. (around 40% of the full load)

Cooling load (%)

Working time (%)

Cooling load (%)

Working time (%)

100 1 50 45

75 42 25 12

Data originate: American Society of Heating, Refrigerating and Air-conditioning Engineers. (ASHRAE)

Ratio of cooling load throughout one year %

2. Adopt digital scroll compressor

Traditional residential split type AC adopts Rotary type compressor;

The efficiency of Scroll type compressor is higher than Rotary type or Reciprocal type compressor;

Energy consumption can be reduced by 10-15% compared with the reciprocal type at the same capability;

Comparing Items Scroll type Rotary typeReciprocal

type

EER 2.9 2.4~2.6 2.2~2.6

Volumetric efficiency 0.99 0.94 0.7

Adiabatic efficiency 0.98 0.93 0.88

Num. of part in compression chamber

1 3 7

Weight ratio 0.8 0.8 1.0

Machining precision 1~3 3 10~30

Output power 1~10 0.4~1 1~10

Core component of digital scroll

Suction Pipe

Discharge Pipe

“Fixed Scroll”by-pass pipe

Orbit Scroll

Variable Capacity Adjustment is achieved by PWM (Pulse-Width-Modulation) valve

Loading

Idling

Gap: 1mm between two scrolls!

Adjust capability output

Pulse-width: Maintain a balance between Demanding and Providing;

“Digital”: loading-100%(1), while Idling-0%(0), forming the sequence

0 1 0 1 0 1 0 1 0 1 0 1 0 1 …..

Digital Multi Unit

Inverter UnitCo

oli

ng

Cap

acit

y

Capacity Demanded

3. Using refrigerant as heat transfer medium

In GMV, heat transferred via refrigerant directly;

The heat amount transferred can be 10 times of those transferred by water, and 20 times via air.

Comparing: Property of heat transfer medium

Types of medium

Utilized heat Transfer amountEnergy consumption (transfer 120 kW cool load)

Water sensible heat 20.1kJ/kg (△t=5℃) 4.8

Air sensible heat 10.1kJ/kg (△t=10℃) 7.5

Refrigerantevaporating latent heat

206kJ/kg 2.6

54% of those transfer via water;

35% of those transfer via air;

4. Sophisticated intelligent controlling

Controlling Object

Forming the network Sensors (temperature, pressure); Throttling devices (electrical expansion valves, pore plates);

Advanced logical algorism; Basic principle

5. Combination with heat recovery processor

To improve the IAQ, people can open the windows sometimes, or install a ventilating fan connect to outside;

But cooling load would rise, and unfiltered air with instable and unreliable factor would penetrate in.

The Fresh Air Heat-Recovery System can solve this problem

• Introduce more filtered fresh air into the room;

• Recycle heat or cooling; (efficiency 75%)

• Reduce the amount of poisonous released from the building material;

The air route inside the system

1. Excellent water absorbability

exchanging efficiency reaches 75%;

2. Super fire-retardant

Safe and reliable

3. Mildew-proof, clean & healthy.

Returning air of indoor

Cooled fresh air introduced in

Exhaust air

Suction of outdoor air

Compared to traditional way of ventilation, Fresh air processor reduces 28% of energy consumption!

Part Ⅳ Digital scroll VS InverterComparing

itemsDigital scroll Inverter

Capabilityadjustment

SEER

Electromagnetic interference

Can be omitted Sever disturbance, expensive electromagnetic-proof apparatus must be installed;

Capacity Shift Shift to 100% capability immediately

Must have procedure of frequency conversion

By-pass of refrigerant

No need Have to install

Digital & common parallel connection

Common Inverter comp. Digital only

Digital Multi Unit

Inverter Unit

Co

oli

ng

Ca

pa

cit

yCapacity Demanded

Summary

WMV can be applied intensively in office building, hotel, luxury department, villa, etc.

Enjoy a high EER/COP under partial load;

Combination with fresh air processor, can improve IAQ & saving energy (up to 30%);

Digital scroll type VRF is more reliable and flexible than Inverter.