Warmliterature.mestek.com/dms/Applied Air/Duct Heaters/TGIFD...a a a a a a a a a aaaa 2 Applied Air Keeps You Warm Applied Air Keeps You Warm In the business of industrial heating,

Indirect FiredDuct FurnacesIndirect FiredDuct Furnaces

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Warm

Applied Air

Keeps You

TGIFD/X-1

Technical Guide for:

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• IFD Two Pass

• IFX Four Pass

IFX Series

IFD Series

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2

Applied Air

Keeps You

Warm

Applied Air

Keeps You

Warm

In the business of industrial heating, efficient and low-cost operation is essential. Applied Airkeeps you warm for less.

Since 1975, Applied Air has been providing cost-effective, reliable heating solutions. Ourproven Indirect Fired Duct Furnaces adds warm clean air to your work environment, butwithout the products of combustion in the airstream.

This Technical Guide will help you choose an Applied Air Indirect Fired Gas Duct Furnace toprovide efficient, cost-effective heating and ventilation for your facility. The Guide covers:

• Technical Specifications — Configure the right system components (e.g., motors, drive,filter, options, etc.) to meet your needs.

– Model “IFD” for two pass units– Model “IFX” for four pass units

• Installation Information — Plan details of on-site installation (dimensions, gas piping, etc.).

If you have questions, please contact Applied Air’s Customer Service Department at 214-638-6010.We’ll be glad to help.

Indirect FiredDuct FurnacesTechnical Guide

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3

Engineering Data – IFD Series ..................................... 4

Dimensions – IFD Series .............................................. 5

Pressure Drop Charts

IFD-160 Duct Furnace ........................................ 6

IFD-320 Duct Furnace ........................................ 7

IFD-480 Duct Furnace ........................................ 8

IFD-800 Duct Furnace ........................................ 9

IFD-1120 Duct Furnace .................................... 10

Typical Gas Piping Layout – IFD Series ...................... 11

Typical Wiring Diagram

IFD-160 & 320 ................................................. 12

IFD-480 ............................................................ 13

IFD-800 & 1120 ............................................... 14

Guide Specification – IFD Series ................................ 15

Engineering Data – IFX Series .............................. 16-17

Dimensions – IFX Series ........................................ 18-19

Pressure Drop Charts

IFX-25 – 40 Duct Furnace ................................ 20

IFX-45 – 55 Duct Furnace ................................ 21

IFX-65 – 75 Duct Furnace ................................ 22

IFX-85 – 100 Duct Furnace .............................. 23

IFX-125 – 175 Duct Furnace ............................ 24

IFX-200 – 250 Duct Furnace ............................ 25

IFX-275 – 300 Duct Furnace ............................ 26

IFX-325 – 400 Duct Furnace ............................ 27

IFX-500 – 600 Duct Furnace ............................ 28

Typical Gas Piping Layout – IFX Series ...................... 29

Typical Wiring Diagram ............................................. 30

Guide Specification – IFX Series ................................ 31

4

Model SizeInput B.T.U./Hour (Maximum)Output B.T.U./Hour(B)Input B.T.U./Hour (Minimum)Natural Gas at 1,000 B.T.U./C.F.Nat. Gas Std. Pipe Size (7” W.C.)Manifold PressureOrifice SizePropane Fuel at 2,500 B.T.U./C.F.L. P. Gas Std. Pipe Size (11” W.C.)Manifold PressureOrifice SizeMinimum AirflowMaximum AirflowCombustion Air Requirements (CFM)Recommended Minimum Stack Size DiameterMaximum Vent Length - Equivalent Length (Ft)Primary Heating Surface – Sq. FeetSecondary Htg. Surface (Tubes & Headers) – Sq. FeetPrimary Combustion Volume – Cu. FeetSecondary Combustion Volume – Cu. FeetTotal Combustion Chamber Volume – Cu. Feet115 Volt, 1 Phase230 Volt, 1 Phase200 Volt, 3 Phase230 Volt, 3 Phase460 Volt, 3 Phase575 Volt, 3 Phase

160 320 480 800 1120200,000 400,000 600,000 1,000,000 1,400,000160,000 320,000 480,000 800,000 1,120,000100,000 100,000 86,000 294,118 435,294

200 400 600 1,000 1,4003/4” 3/4” 1” 1” 1-1/4”1.5 2.8 4.7 2.0 2.0#4 NR NR NR NR80 160 240 400 560

3/4” 3/4” 1” 1” 1-1/4”1.5 2.2 2.5 1.7 1.2#2 #6 NR NR NR

1,481 2,963 4,444 7,407 10,3704,938 9,877 14,815 24,691 34,568

39 77 115 192 2684” 6” 7” 9” 10”50 50 50 50 50

13.49 21.35 32.97 51.21 66.6516.23 27.87 45.75 65.46 94.183.47 6.94 12.73 25.75 39.490.93 1.74 2.76 4.22 5.644.40 8.68 15.49 29.97 45.138.70 8.70 13.04 13.04 13.044.35 4.35 6.52 6.52 6.525.00 5.00 7.50 7.50 7.504.35 4.35 6.52 6.52 6.522.17 2.17 3.26 3.26 3.261.74 1.74 2.61 2.61 2.61

SIZE &CAPACITY

FIRING RATE &MANIFOLD SIZE

SUPPLY AIRCAPACITY

COMBUSTION AIR& VENTING

REQUIREMENTSINTERNAL DATA OFHEAT EXCHANGER

(A)

AMP DRAW

Engineering Data – IFD Series

Capacity and Internal Data

(A) Standard construction - 400 series stainless steel primary and secondary material.

(B) Based on 80% operating efficiency.

5

ApproximateWeight 508 685 83712371713

Dimensions

Models IFD Duct Furnaces C000554

160320480800

1120

Dimensions" D"599

101/410

" C"5058748386

" B"3040424959

" A"2430324151

" E" " H"157/8157/8157/8

20249/16

" K"109/16159/16159/16171/16179/16

10121/2

151928

IFDModel " F"

4654707982

" G"4654707982

" J"51/267/16

771/1687/8

NOTE: All dimensions in inches subject to manufacturing tolerances.

±4±4±4±4±14

6

Pressure Drop Chart

Model IFD-160

IFD

160

Air

Sid

e P

ress

ure

Dro

p -

8 i

nch

pro

file

0.00

0.10

0.20

0.30

0.40

0.50

0.60

1400

1800

2200

2600

3000

3400

3800

4200

4600

5000

CF

M

Pressure Drop - Inches Water Column

7

Pressure Drop Chart

Model IFD-320

IFD

320

Air

Sid

e P

ress

ure

Dro

p -

Ave

rag

ed

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

2800

3800

4800

5800

6800

7800

8800

9800

CF

M


8

Pressure Drop Chart

Model IFD-480

IFD

480

Air

Sid

e P

ress

ure

Dro

p -

Ave

rag

ed

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

4400

5400

6400

7400

8400

9400

1040

011

400

1240

013

400

1440

0

CF

M


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Pressure Drop Chart

Model IFD-800

IFD

800

Air

Sid

e P

ress

ure

Dro

p -

Ave

rag

ed

0

0.2

0.4

0.6

0.81

1.2

1.4

1.6 7

00

09

00

01

10

00

13

00

01

50

00

17

00

01

90

00

21

00

02

30

00

25

00

0

CFM

Pressure Drop - inches Water Column

10

Pressure Drop Chart

Model IFD-1120

IFD

112

0 A

ir S

ide

Pre

ssu

re D

rop

- A

vera

ged

0

0.2

0.4

0.6

0.81

1.2

1.4

1.6 1

0000

1200

014

000

1600

018

000

2000

022

000

2400

026

000

2800

030

000

3200

034

000

CFM


11

Gas Piping Layout

Schematic Component Diagrams

NOTES:1. Vent limiting devices provided wherever possible, when venting is required the venting to

outside is by others on indoor units and furnished by factory on outdoor units.

2. For inlet pressures under 7” W.C. please consult factory.

C000558

COMPONENT IDENTIFICATIONGP-01 HIGH GAS PRESSURE REGULATOR (OPTIONAL)GP-05 MAIN GAS PRESSURE REGULATORGP-09 PILOT GAS PRESSURE REGULATORGP-11 FIRING VALVEGP-13 PILOT FIRING VALVEGP-27 NEEDLE ORIFICE VALVEGP-39 BUTTERFLY VALVEMT-11 MODULATING VALVE MOTOR

*VG-01 PILOT GAS VALVEVG-02 MAIN GAS VALVEVG-03 AUXILARY GAS VALVEVG-04 N/O VENT VALVEPS-02 BURNER AIR FLOW SWITCHPS-04 LOW GAS PRESSURE SWITCHPS-07 HIGH GAS PRESSURE SWITCH

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Wiring Diagram

Typical Wiring Diagram – IFD-160 & 320 C000560

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Wiring Diagram

Typical Wiring Diagram – IFD-480 C000559

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Wiring Diagram

Typical Wiring Diagram – IFD-800 Through 1120 C000561

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Guide Specification – IFD Series

Base Bid Applied Air Model IFD ______________ Indirect FiredDuct Furnace. The unit shall be factory fabricated, assembled, wiredand tested prior to shipment in accordance with the specification andequipment schedule. The unit will include all components herein andas shown on the drawings. Alternate equipment, equal in design,construction, performance and capacity to unit(s) specified, must beshown with price deduct/add, if any. Approval of alternateequipment will be subject to review of shop drawings. The unit shallbe capable of handling______SCFM. The unit shall be ETL listed.

CASINGThe unit casing shall consist of formed 18 gauge galvanized steelpanels to ensure rigid construction. Cabinet design shall allow unit(s)to be mounted in the horizontal arrangement with no externalframework. The casing enclosing the heat exchanger shall be ofdouble wall construction with a galvanized steel inner wall serving asa radiation shield. Radiation and transmission losses shall not exceed2% of the rated input. The casing enclosing the heat exchanger shallbe insulated with 1", 11/2 lb. density fiberglass insulation.

HEAT EXCHANGERThe entire primary and secondary heat transfer surface shall be 400series stainless steel. The heat exchanger design shall permitunrestricted lateral and peripheral expansion during the heating andcooling cycle. The flue gas travel shall be of two-pass design, withinternal baffles in the secondary tubes. The surface temperature ofthe heat exchanger shall not exceed 75% of its scaling temperaturewhen operating at rated capacity. The heat exchanger shall be ratedat a minimum of 80% efficiency throughout complete operatingrange.

BURNERThe gas burner shall be of the power type, complete with integralcombustion air blower and motor, combustion air proving switch, andremovable pilot assembly. Burner shall be complete with anobservation window to view the flame. The combustion air dampershall be interlocked with the gas control valve to insure a proper gas/air mixture throughout the complete range of operation. Burner andcontrols shall be capable of delivering ______MBH output firing on(natural gas) (propane) at an inlet pressure of _________(inches water column) (PSIG). The standard ETL listed unit will meetANSI, FM, and IRI requirements. Burner and controls shall bearranged for full modulation with low fire start and a _____turndown ratio. Burner combustion shall be on-ratio throughout thecomplete operating range. The factory wired and piped valve trainshall be complete with:

• low pressure appliance regulator

• motorized gas control valve

• main manual test firing shut-off valve

• main automatic shut-off valve(s)

• pilot manual shut-off valve (Models 480 & larger)

• pilot pressure regulator (Models 480 & larger)

• pilot automatic shut-off valve (Models 480 & larger)

• pilot manual test firing shut-off valve (Models 480 & larger)

ELECTRICAL CONTROLSA factory wired NEMA 1 control panel complete with hinged accessdoor and 10 foot wiring harness shall be shipped with duct furnace.All control components are to be labeled and individually wired to anumbered terminal strip to aid in servicing. All wiring shall be colorcoded and number tagged at each end to match the control diagramsupplied. Full operating and maintenance instructions shallaccompany each unit. All wiring between the controls and valves shallbe run in flexible conduit. All electrical components shall bear the U.L.label. The control system shall include but not be limited to thefollowing components required for automatic operation:

• control circuit transformer

• control circuit fuses

• control relays

• electronic flame relay

• high limit switch

• automatic/manual fan switch

• spark generator (Models 160-480)

• heavy duty ignition transformer (Models 800-1120)

16

Model SizeInput MBHOutput MBH(A)Natural Gas @ 1,000 B.T.U./C.F.Gas Connection @ 7” W.C. (Natural Gas)Gas Connection @ 14” W.C. (Natural Gas)Combustion Air Required (C.F.M.)Exhauster ModelExhauster H.P.Burner H.P.Recommended Min. Stack Size – Dia.200 Volt, 3 Phase230 Volt, 3 Phase460 Volt, 3 Phase575 Volt, 3 Phase

25 35 40 50 55312 437 500 625 687250 350 400 500 550312 437 500 625 6873/4” 3/4” 1” 1” 1”3/4” 3/4” 3/4” 3/4” 1”80 110 130 160 18012 12 12 12 12

1/3 1/3 1/3 1/3 1/31/3 1/3 1/3 1/3 1/38” 8” 8” 8” 8”

21.9 21.9 16.3 16.3 16.320.9 20.9 15.1 15.1 15.117.7 17.7 11.2 11.2 11.217.0 17.0 10.4 10.4 10.4


SIZE &CAPACITY


EQUIPMENT DATA

AMP DRAW (B)

65 75 85 100 125812 987 1,062 1,250 1,562650 750 850 1,000 1,250812 987 1,062 1,250 1,562

11/4” 11/4” 11/4” 11/2” 11/2”1” 1” 1” 1” 11/4”

210 240 275 325 40012 12 14 14 18

1/3 1/3 1/2 1/2 21/3 1/3 1/3 1/3 1/210” 10” 10” 10” 12”16.3 16.3 17.2 19.7 26.715.1 15.1 15.9 18.1 24.511.2 11.2 11.6 12.6 17.110.4 10.4 10.7 11.6 15.7

SIZE &CAPACITY

FIRING RATE &MANFOLD SIZE

EQUIPMENT DATA

AMP DRAW (B)

Engineering Data – IFX Series


(A) Based on 80% operating efficiency.

(B) Based on G-P burners.

17


150 175 200 250 2751,875 2,187 2,500 3,125 3,4381,500 1,750 2,000 2,500 2,7501,875 2,187 2,500 3,125 3,438

2” 2” 2” 2” 21/2”11/2” 11/2” 11/2” 2” 2”480 560 650 800 88018 18 18 21 212 2 2 3 3

1/2 1/2 1/2 1 112” 12” 12” 12” 14”26.7 27.6 27.6 19.6 19.624.5 25.3 25.3 17.1 17.117.1 17.5 17.5 8.5 8.515.7 16.0 16.0 6.8 6.8


SIZE &CAPACITY


EQUIPMENT DATA

AMP DRAW (B)

300 350 400 500 6003,750 4,375 5,000 6,250 7,5003,000 3,500 4,000 5,000 6,0003,750 4,375 5,000 6,250 7,50021/2” 3” 3” NA NA

2” 2” 21/2” 3” 3”960 1,120 1,300 1,600 1,92021 21 21 21 213 3 3 5 51 1-1/2 2 3 5

14” 14” 14” 18” 18”19.6 21.7 22.6 32.3 38.717.1 18.9 19.7 28.1 33.78.5 9.4 9.8 14.0 16.86.8 7.5 7.9 11.2 13.5

SIZE &CAPACITY

FIRING RATE &MANFOLD SIZE

EQUIPMENT DATA

AMP DRAW (B)

Engineering Data – IFX Series


(A) Based on 80% operating efficiency.

(B) Based on G-P burners.

18

Dimensions

Model IFX Duct Furnaces P000898A

19

"J"63/863/863/863/863/863/873/873/873/873/893/893/893/893/893/8

111/8111/8111/8111/8111/8111/8111/8111/8111/8

25-4055/4075/4045-5575/55

100/5565-75

100/7585-100

175/100125-175250/175

200300/200400/200

250300/250400/250275-300400/300600/300325-400600/400500-600

Dimensions

Model IFX Duct FurnacesDimensions

"D"79999

159

151515151515

171/22015

171/220

171/22016201616

"C"4456765676867686869696

116116136154116136154136154174154174174

"B"9

11101/2

11101/2

14101/2

1414161621192121212121212123212323

"A"111/2121/2123/4121/2123/4

17123/4

17171919

191/2201/2

22241/2191/2

22241/2

22241/2281/2241/2281/2281/2

"E"181818181818181818242430303030303030303048304848

"G"242424282828282832323737373737373737434343

571/4571/4793/4

"K"13131315151515152424

221/2221/2221/2221/2221/2221/2221/2221/2

272727

311/4311/4461/4

"L"474747555555555568687272727272727272848484

100100141

"M"10101012121212121212

121/2121/2121/2121/2121/2121/2121/2121/2

141414

111/2111/2

15

Model "F"61/461/461/461/461/461/4

777799999

105/8105/8105/8105/8105/8105/8105/8105/8105/8

"H"323636363648364848545460606570606570657080708080

NOTE: All dimensions in inches subject to manufacturing tolerances.

ApproximateWeight102511001220128013551688160018332250247531803230422541715444440045375716550060026423660068518871

"X"65/885/885/885/885/8

145/871/4

131/4131/4161/4131/4161/4161/4163/8187/8137/8163/8187/8163/8187/8237/8187/8237/8237/8

25-4055/4075/4045-5575/55

100/5565-75

100/7585-100

175/100125-175250/175

200300/200400/200

250300/250400/250275-300400/300600/300325-400600/400500-600

Dimensions"S"24444

104

1051/481/4

58

73/897/8

123/873/897/8

123/84

61/2111/261/2

111/261/4

"R"222222

31/431/431/231/231/231/223/823/823/823/823/823/821/221/221/233/433/4

4

" P"171717171717171717172121212121262626262626323232

"N"191/4191/4191/4211/4211/4211/4211/4211/4203/4203/4223/4223/4223/4223/4223/4223/4223/4223/4261/4261/4261/4211/4211/4271/4

"T"2828282828282828

371/2371/2

4444

451/4451/4451/4451/4451/4451/4

5757575757

671/2

"V"466

51/851/8

111/851/8

111/867/8

111/851/297/861/281/2

961/281/2

96

81/2131/281/2

131/281/2

"Y"999999

101/2101/2101/2101/2131/2131/2131/2131/2131/2151/2151/2151/2151/2151/2151/2151/2151/2151/2

"Z"81/481/481/481/481/481/491/291/291/291/21313131313

141/4141/4141/4141/4141/4141/4141/4141/4141/4

"AA"201/4201/4201/4201/4201/4201/4221/4221/4213/4221/4213/4213/4253/4253/4253/4253/4331/4311/4321/4253/4321/4331/4331/4311/4

Model "U"161616161616161616161616

211/4211/4211/4211/4211/4211/4

272727272725

" W"486080608090809090

100100120120140160120140160140160180160180180

ApproximateWeight102511001220128013551688160018332250247531803230422541715444440045375716550060026423660068518871

20

Pressure Drop Chart

Model IFX-25-40

Siz

e 25

-40

0.0

00

.05

0.1

00

.15

0.2

0

0.2

50

.30

0.3

50

.40

0.4

50

.50 2

,500

2,70

02,

900

3,10

03,

300

3,50

03,

700

3,90

04,

100

4,30

04,

500

4,70

04,

900

5,10

05,

300

5,50

0

CF

M

Static pressure drop (inches w.c.)

21

Pressure Drop Chart

Model IFX-45-55

Siz

e 45

-55

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

4,90

05,

100

5,30

05,

500

5,70

05,

900

6,10

06,

300

6,50

06,

700

6,90

07,

100

7,30

0

CF

M


22

Pressure Drop Chart

Model IFX-65-75

Siz

e 65

-75

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

7,00

07,

500

8,00

08,

500

9,00

09,

500

10,0

00

CFM


23

Pressure Drop Chart

Model IFX-85-100

Siz

e 85

-100

0.1

0

0.1

5

0.2

0

0.2

5

0.3

0

0.3

5

0.4

0

0.4

5

0.5

0 9,0

009,

500

10,0

0010

,500

11,0

0011

,500

12,0

0012

,500

13,0

00

CFM


24

Pressure Drop Chart

Model IFX-125-175

Siz

e 12

5-17

5

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.55 1

3,00

014

,000

15,0

0016

,000

17,0

0018

,000

19,0

0020

,000

21,0

0022

,000

23,0

00

CFM


25

Pressure Drop Chart

Model IFX-200-250

Siz

e 20

0-25

0

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50 2

1,00

022

,000

23,0

0024

,000

25,0

0026

,000

27,0

0028

,000

29,0

0030

,000

31,0

0032

,000

33,0

00

CF

M


26

Pressure Drop Chart

Model IFX-275-300

Siz

e 27

5-30

0

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50 2

9,00

030

,000

31,0

0032

,000

33,0

0034

,000

35,0

0036

,000

37,0

0038

,000

39,0

00

CF

M

Static pressure drop

(inches w.c.)

27

Pressure Drop Chart

Model IFX-325-400

Siz

e 32

5-40

0

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50 3

5,00

037

,000

39,0

0041

,000

43,0

0045

,000

47,0

0049

,000

51,0

0053

,000

CF

M


28

Pressure Drop Chart

Model IFX-500-600

Siz

e 50

0-60

0

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50 5

5,00

057

,000

59,0

0061

,000

63,0

0065

,000

67,0

0069

,000

71,0

0073

,000

75,0

0077

,000

79,0

0081

,000

CF

M


29

Gas Piping Layout

Schematic Component Diagrams

NOTES:1. *Vent limiting devices provided wherever possible, when venting is required the venting to

outside is by others on indoor units and furnished by factory on outdoor units.

2. All models require 7” W.C. minimum inlet pressure. Contact factory for inlet pressuresbelow this minimum.

C000528

COMPONENT IDENTIFICATIONGP-01 HIGH GAS PRESSURE REGULATORGP-05 MAIN GAS PRESSURE REGULATORGP-09 PILOT PRESSURE REGULATORGP-11 MAIN GAS SHUT-OFF VALVE (SHIP LOOSE)GP-13 PILOT GAS SHUT-OFF VALVEGP-18 AUXILIARY GAS SHUT-OFF VALVEGP-27 ORIFICED NEEDLE VALVEGP-39 BUTTERFLY VALVE

MT-11 BUTTERFLY VALVE OPERATOR(MODULATING BURNERS ONLY)

PS-01 DRAFT PROVING SWITCHPS-02 BURNER AIR FLOW SWITCHPS-04 LOW GAS PRESSURE SWITCHPS-07 HIGH GAS PRESSURE SWITCHVG-01 PILOT GAS VALVEVG-02 MAIN GAS VALVEVG-03 AUXILIARY GAS VALVEVG-04 N/O VENT VALVE

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Wiring Diagram

Typical Wiring Diagram – IFX C000565

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31

Base Bid Applied Air Model IFX ______________ Indirect FiredDuct Furnace. The unit shall be factory fabricated, assembled, wiredand tested prior to shipment in accordance with the specification andequipment schedule. The unit will include all components herein andas shown on the drawings. Alternate equipment, equal in design,construction, performance and capacity to unit(s) specified, must beshown with price deduct/add, if any. Approval of alternateequipment will be subject to review of shop drawings. The unit shallbe capable of handling______SCFM. The unit shall be ETL listed.

CASINGThe unit casing is to be panel construction from 16 gauge galvanizedsteel, suitably reinforced to ensure rigidity. All panels shall be factorysealed with caulking between mating panels. The casing enclosingthe heat exchanger shall be of double wall construction with agalvanized steel inner wall serving as a radiation shield. Radiationand transmission losses shall not exceed 11/2% of the rated output.This section shall be insulated with 1", 11/2 lb. density insulation.

The unit shall have an integral milled channel base complete withlifting lugs.

INDIRECT GAS FIRED SECTIONThe entire primary heat transfer surface and header shall be of 400series stainless steel; the secondary heat transfer surface shall be(mild steel) (400 series stainless steel). The heat exchanger designshall permit unrestricted lateral and peripheral expansion during theheating and cooling cycle. The flue gas travel shall be of four-passdesign, with no internal baffles. The surface temperature of the heatexchanger shall not exceed 75% of its scaling temperature whenoperating at rated capacity. The heat exchanger shall be rated at aminimum of 80% efficiency at rated output. A pressure relief doorcomplete with an observation window to view the complete flameand pilot shall be provided.

DIRECT DRIVE INDUCED DRAFT FANAn integrally mounted, heavy duty, non-clogging radial blade induceddraft fan complete with direct drive motor shall be provided. Theinduced draft fan shall be adequately sized to insure proper draftconditions when operating at rated capacity and equipped with amanual damper complete with locking quadrant to ensure properdraft and extended heat exchanger performance.

BURNERThe gas burner shall be of the power type, complete with integralcombustion air blower and motor, combustion air proving switch, andremovable pilot assembly. The combustion air damper shall beinterlocked with the gas control valve to insure a proper gas/airmixture throughout the complete range of operation. Burner andcontrols shall be capable of delivering ______MBH output firing on(natural gas) (propane) at an inlet pressure of _________(inches water column) (PSIG) and in accordance with(manufacturer's standard) (FM) (IRI) requirements. Burner andcontrols shall be arranged for ((High/Low/Off) (Full Modulation withlow fire start and up to a 10:1 turndown ratio). The factory wiredand piped valve train shall be mounted inside the unit weatherproofenclosure and be complete with:

• low pressure appliance regulator

• motorized gas control valve

• main manual test firing shut-off valve

• pilot manual shut-off valve

• pilot pressure regulator

• pilot automatic shut-off valve

• pilot manual test firing shut-off valve

ELECTRICAL CONTROLSA NEMA 1 control panel complete with hinged access door shall beprovided. All control components are to be labeled and individuallywired to a numbered terminal strip to aid in servicing. All wiring shallbe color coded and number tagged at each end to match the controldiagram supplied. Full operating and maintenance instructions shallaccompany each unit. All wiring between the controls and valves shallbe run in flexible conduit. All electrical components shall bear the U.L.label. The control system shall include but not be limited to thefollowing components required for automatic operation:

• control circuit transformer

• control circuit fuses

• control relays

• electronic flame relay complete with alarm contacts

• induced draft fan air proving differential switch

• high limit switch

• automatic/manual fan switch

• heavy duty ignition transformer

Guide Specification – IFX Series

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EfficientIndirect FiredDuctFurnaces

Applied Air

www.appliedair.com

4830 Transport Drive Dallas TX 75247

Telephone 214.638.6010

Fax 214.905.0806

Choose Applied Air Indirect Gas Duct Furnaces• Provide space heating or make-up air without products of combustion in the supply air

• Low operating and maintenance costs

• Simple, inexpensive installation

• Applied Air, a leader in research, engineering, and customer service since 1975

IFX Series

IFD Series

Documents

Warmliterature.mestek.com/dms/Applied Air/Duct Heaters/TGIFD...a a a a a a a a a aaaa 2 Applied Air Keeps You Warm Applied Air Keeps You Warm In the business of industrial heating,