Troubleshooting Charts. Cozy Hi-Efficient Direct Vent

SYMPTOM

Flame

Too Large

Yellow

Burner Flame

Gas Odor

Delayed

Ignition

Failure to Ignite

Burner Won’t

Turn Off

Incorrect

Gas Input

Not

Enough

Heat

Too Much

Heat

Main Burner

Goes Out

During

Normal

Operation

POSSIBLE CAUSES

1. Defective operator section of valve.

2. Burner orifice too large.

3. If installed above 2,000 ft.

1. Clogged burner ports.

2. Obstruction around vent cap.

1. Gas leak.

1. Low gas pressure.

2. Igniter not properly located.

1. Main gas off.

2. Thermostat not set high enough to call for heat.

3. Clogged burner orifice.

4. Incorrect wiring.

5. Defective valve.

6. No power to unit.

1. Defective or damaged thermostat wire or thermostat.

2. Thermostat location.

3. Defective or sticking valve.

4. Excessive gas pressure.

5. Defective or damaged thermostat.

1. Gas input not checked.

2. Clogged orifices.

1. Furnace undersized.

2. Thermostat temperature set too low.

3. Incorrect supply pressure.

1. Temperature set too high.

2. Combination control valve stuck open.

1. Defective flame sensor.

2. Input too high.

3. Sight glass not air tight.

4. Vent tubes not properly installed or sealed.

5. Limit switch opens.

6. Exhaust or Air Intake tubes blocked.

TROUBLESHOOTING CHART

For use by a qualified service technician.

CORRECTIVE ACTION - (To be performed by Contractor)

1. Replace valve.

2. Check with local gas company for proper orifice - size and replace.

3. See burner orifice section, Page 12.

1. Remove burners and check for obstructions in throats, ports, and orifices. Clean - but do not enlarge ports or orifices.

2. Make sure area around vent cap is clear, be sure vent system is sealed.

1. See Page 1.

1. Check gas supply pressure.

2. Check ignitor location and correct if necessary.

1. Open manual gas valve.

2. Set thermostat to higher temperature.

3. Clean burner orifices (do not enlarge).

4. Check wiring diagram.

5. Replace valve.

6. Plug in power supply cord. Check 115 V. wall outlet.

1. Can be checked by removing wire from control board terminal.

If burner goes off, replace thermostat.

2. Re-locate out of drafts, hot, or cold spots.

3. Replace valve.

4. Contact utility supplying gas.

5. Replace thermostat.

1. Re-check gas input.

2. Clean orifices with a smooth wood toothpick, do not enlarge.

1. This is especially true when a dwelling or room is enlarged. Have the heat loss calculated and compare to furnace output. Your gas company can supply you with this information. If furnace is undersized, replace with correct size unit.

2. Raise thermostat temperature setting.

3. Check supply pressure.

1. Lower temperature setting.

2. Replace combination control valve.

1. Check voltage and replace if low.

2. Check input rate.

3. Tighten screws securing sight glass. Check & replace gasket if needed.

4. Follow instructions. Check both exhaust and air intake tubes, and vent cap.

Be sure all gaskets are in place and properly sealed. Use only tubes and vent cap supplied. Do not alter vent tubes or cap.

5. Check for blockage of discharge air.

6. Check for and remove any obstruction to incoming circulating air.

1017952-A Page 20

TROUBLESHOOTING CHART

For use by a qualified service technician.

To assist in diagnosing and servicing, this heater is equipped with a self-diagnosing control module. Should a malfunction occur, the green indicator light on the control module will flash a varying number of times indicating the circuit in which malfunction is located.

Slow

Flash

Fast

Flash

2

# OF

FLASHES

REASON FOR

INDICATION

Normal Operation,

NO CALL FOR HEAT

Normal Operation,

CALL FOR HEAT

System Lockout

Failed to Detect or

Sustain Flame

POSSIBLE

CAUSES

CORRECTIVE ACTION

(To be performed by Contractor)

3

4

Pressure

Switch Open or Closed

Limit Switch

Opens

5 Flame Sensed

Gas Valve

Not Energized

Steady

Light - No

Flashes

Internal Failure

(Control module failure and power on self-check)

1. Defective ignitor.

2. Ignitor cable defective.

3. Ignitor cable disconnected.

4. Manual gas valve in “ OFF ” position. No gas to valve.

5. Defective wire to gas valve.

6. Wire to gas valve disconnected.

7. Obstruction to vent outlet.

8. Obstruction to air inlet.

1. Defective pressure switch.

2. Pressure switch tubing damaged, kinked or collapsed.

3. Pressure switch tubing disconnected.

4. Defective draft inducer.

5. Pressure switch tubing to the wrong connection.

1. Defective limit switch.

2. Damaged limit switch wire.

3. Limit switch wire disconnected.

4. Blockage in front of front panel.

5. Heater over rate.

1. Defective gas valve.

2. Defective control module.

1. Replace ignitor.

2. Replace ignitor cable.

3. Connect ignitor cable.

4. Turn manual gas valve to “ ON .”

5. Replace defective wire.

6. Connect gas valve wire.

7. Remove obstruction.

8. Remove obstruction.

1. Replace pressure switch.

2. Replace damaged tubing.

3. Connect pressure switch tubing.

4. Replace draft inducer.

5 Reverse tubing connections on pressure switch.

1. Replace limit switch.

2. Replace damaged wire.

3. Connect limit switch wire.

4. Remove blockage.

5. Check orifice, pressures, rate.

1. Replace gas valve.

2. Replace control module.

1. Defective control module. 1. Replace control module.

Page 21 1017952-A

HI-EFFICIENT DIRECT VENT WALL FURNACE PARTS LIST

Natural Gas: HEDV253A & HEDV403A | Propane Gas: HEDV254A & HEDV404A

2

1

4

44

40

5

3

HOW TO

PROPERLY

ORDER PARTS:

In addition to the part description and numbers, please be prepared to provide:

- Model Number

- Serial Number

- Type of Gas Used

This information can be found on the rating plate that is attached to the heater.

REF. #

1

2

3

4

5

6

7

8

9

10

11

12

13

14

PART DESCRIPTION

Cabinet

Circulating Blower

Limit Switch

Front Heat Shield

Tubular Heat Exchanger

Cabinet Base Assembly

Leg Leveler - (4 Per)

Draft Inducer Gasket - ( 7-3/4 x 9” )

Draft Inducer - (Mounting Plate Gasket)

Draft Inducer

Sight Glass Frame

Sight Glass

Sight Glass Gasket - ( 2-5/8 x 1-3/8” )

Ignitor

6

42

30

31

9

29

25

26 41

34

36

38

23

35

36

37

47

24

28

8

11

24

10

12 13

16

22

20

21

19

17

18

27

33

14

43

15

46

32

PART #

HEDV253A

PART #

HEDV254A

PART #

HEDV403A

PART #

HEDV404A

18020 18020 18520 18520

72501 72501 72500 72500

72671 72671 72670 72670

72531 72531 72530 72530

18120 18120 18620 18620

18120 18120 18620 18620

80009 80009 80009 80009

72565 72565 72565 72565

72563 72563 72563 72563

72506 72506 72506 72506

18185 18185 18185 18185

70150 70150 70150 70150

72564 72564 72564 72564

64009 64009 64009 64009

1017952-A

NOTE: Parts & schematic drawings on current models are shown at: cozyheaters.com | Specifications subject to change without notice.

Page 22