CGN20TA

Blue Flame Vent-Free Natural Gas Heater

TROUBLESHOOTING

Note: All troubleshooting items are listed in order of operation.

WARNING: Turn off and un- plug heater and let cool before servicing. Only a qualified ser- vice person should service and repair heater.

CAUTION: Never use a wire, needle, or similar object to clean ODS/pilot. This can damage ODS/ pilot unit.

OBSERVED PROBLEM

POSSIBLE CAUSE

REMEDY

When ignitor button is pressed, there is no

1.

Ignitor electrode positioned wrong

1.

Replace ignitor

spark at ODS/pilot

2.

Ignitor electrode broken

2.

Replace ignitor

 

3.

Ignitor electrode not connected to igni-

3.

Reconnect ignitor cable

 

 

tor cable

 

 

 

4.

Ignitor cable pinched or wet

4.

Free ignitor cable if pinched by any

 

 

 

 

metal or tubing. Keep ignitor cable dry

 

5.

Piezo ignitor nut is loose

5.

Tighten nut holding piezo ignitor to

 

 

 

 

heater cabinet. Nut is located inside

 

 

 

 

heater cabinet at top

 

6.

Broken ignitor cable

6.

Replace ignitor cable

 

7.

Bad piezo ignitor

7.

Replace piezo ignitor

 

 

 

 

 

When ignitor button is pressed, there is

1.

Gas supply turned off or manual shutoff

1.

Turn on gas supply or open manual

spark at ODS/pilot but no ignition

 

valve closed

 

shutoff valve

 

2.

Control knob not in PILOT position

2.

Turn control knob to PILOT position

 

3.

Control knob not pressed in while in PI-

3.

Press in control knob while in PILOT

 

 

LOT position

 

position

 

4.

Air in gas lines when installed

4.

Continue holding down control knob.

 

 

 

 

Repeat igniting operation until air is re-

 

 

 

 

moved

 

5.

ODS/pilot is clogged

5.

Clean ODS/pilot (see Cleaning and

 

 

 

 

Maintenance, page17) or replace ODS/

 

 

 

 

pilot assembly

 

6.

Gas regulator setting is not correct

6.

Replace gas regulator

 

 

 

 

 

ODS/pilot lights but flame goes out when

1.

Control knob not fully pressed in

1.

Press in control knob fully

control knob is released

2.

Control knob not pressed in long enough

2.

After ODS/pilot lights, keep control

 

 

 

 

knob pressed in 30 seconds

 

3.

Safety interlock system has been trig-

3.

Wait one (1) minute for safety interlock

 

 

gered (Thermostat models only)

 

system to reset. Repeat ignition operation

 

4.

Manual shutoff valve not fully open

4.

Fully open manual shut-off valve

 

5.

Thermocouple connection loose at con-

5.

Hand tighten until snug, then tighten 1/4

 

 

trol valve

 

turn more

 

6.

Pilot flame not touching thermocouple,

6.

A) Contact local natural gas company

 

 

which allows thermocouple to cool,

 

B) Clean ODS/pilot (see Cleaning and

 

 

causing pilot flame to go out. This prob-

 

Maintenance, page 17) or replace ODS/

 

 

lem could be caused by one or both of

 

pilot assembly

 

 

the following:

 

 

 

 

A) Low gas pressure

 

 

 

 

B) Dirty or partially clogged ODS/

 

 

 

 

pilot

 

 

 

7.

Thermocouple damaged

7.

Replace thermocouple

 

8.

Control valve damaged

8.

Replace control valve

14

104190

Page 14
Image 14
Desa Tech CGN20TA installation manual Troubleshooting, Observed Problem Possible Cause Remedy