Troubleshooting

WARNING: Turn off heater and let cool before servicing. Only a qualified service person should service and repair heater.

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

Note: Before troubleshooting the system, make sure the gas shutoff valve is ON. The two most common causes of a malfunctioning gas appliance are:

1.Loose wiring connections

2.Construction debris clogging the pilot and/or gas control valve filter

OBSERVED PROBLEM

POSSIBLE CAUSE

REMEDY

 

 

 

 

 

Ignitor will not spark or pilot

1. No gas supply or shutoff

1.

Check to see if you have gas

will not light

 

valve is OFF

 

supply and that equipment

 

2.

Air in gas line

2.

shutoff valve is opened

 

Repeat lighting procedure sev-

 

 

 

 

eral times to purge all air out of

 

 

 

 

lines. If after repeated attempts

 

 

 

 

appliance does not light, call for

 

3.

Construction debris clogging

3.

qualified service and repair.

 

Remove debris and dirt, in-

 

 

pilot orifice

 

spect and clean any other

 

4.

Low gas pressure

4.

possible obstructions

 

Contact your gas supplier to

 

5.

Kinked pilot line

5.

check pressure

 

Have a qualified technician

 

6.

Control valve is not opening

6.

replace pilot line

 

Replace control valve (refer to

 

7.

No power to unit or the

7.

Replacement Parts, page 32)

 

Check that main power is on

 

 

ignition module or power

 

and that all wire connections

 

 

transformer is bad

 

are made correctly to the

 

 

 

 

ignition model (see Wiring

 

 

 

 

Diagram, page 26). Check for

 

 

 

 

24 VAC at the secondary side

 

 

 

 

of the transformer. If 24 VAC

 

 

 

 

is present and the module does

 

 

 

 

not operate, have the module

 

 

 

 

replaced otherwise have the

 

8.

Vent damper not fully open

8.

transformer replaced

 

Open vent damper until fully

 

 

 

 

locked in OPEN position

 

 

 

 

 

Pilot will not stay lit

1. Loose wiring on ignitor wire

1.

Check wiring connection.

 

 

to ignition module and/or

 

Refer to wiring diagram (see

 

 

poor ground to ignition mod-

 

Wiring Diagram, page 26)

 

 

ule

 

and/or check ground wire to

 

2. Pilot flame too low to sense

2.

ignition module

 

Clean and adjust pilot burner

 

 

 

 

and check gas supply and inlet

 

 

 

 

pressure to unit

 

 

 

Note: Have a qualified technician

 

 

 

replace pilot assembly if broken

 

 

 

or corroded

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Desa (V)T32EP-A SERIES, (V)T32EN-A SERIES installation manual Troubleshooting, Observed Problem Possible Cause Remedy