34

TROUBLESHOOTING

Electronic Ignition System

TROUBLESHOOTING

Electronic Ignition System

Note: For additional help, visit DESA’s technical service web site at

www. desatech.com

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

WARNING: Turn off heater and

 

CAUTION Never use a wire,

let cool before servicing.Only a quali-

 

needle, or similar object to

fied service person should service

 

clean pilot. This can damage

and repair heater.

 

pilot unit.

 

 

 

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 will not light

1.

No gas supply, or shutoff valve is OFF

1.

Check to see if you have gas supply and

 

 

 

 

that equipment shutoff valve is opened

 

2.

Air in gas line

2.

Repeat lighting procedure several times

 

 

 

 

to purge all air out of lines. If after re-

 

 

 

 

peated attempts appliance does not light,

 

 

 

 

call for qualified service and repair.

 

3.

Construction debris clogging pilot orifice

3.

Remove debris and dirt, and inspect and

 

 

 

 

clean any other possible obstructions

 

4.

Low gas pressure

4.

Contact your gas supplier to check

 

 

 

 

pressure

 

5.

Kinked pilot line

5.

Have a qualified technician replace pi-

 

 

 

 

lot line

 

6.

Control valve is not opening

6.

Replace control valve (Refer to Replace-

 

 

 

 

ment Parts, page 36)

 

7.

No power to unit or the ignition module

7.

Check that main power is on and that

 

 

 

 

wire connections are made correctly to

 

 

 

 

the ignition model (see Wiring Diagram,

 

 

 

 

page 19). Check for 24 VAC at the sec-

 

 

 

 

ondary side of the transformer. If 24

 

 

 

 

VAC is present, and the module does not

 

 

 

 

operate, have the module replaced oth-

 

 

 

 

erwise have the transformer replaced.

 

 

 

 

 

Pilot will not stay lit

1.

Loose wiring on ignitor wire to ignition

1.

Check wiring connection. Refer to wir-

 

 

module and/or poor ground to ignition

 

ing diagram (see Wiring Diagram, page

 

 

module

 

19) and/or check ground wire to igni-

 

 

 

 

tion module

 

2.

Pilot flame too low to sense

2.

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

Frequent outage of main burner and pilot

1.

Pilot flame may be too low to sense flame

1.

Cleanandadjustpilotflameformaximum

after complete ignition sequence.

 

causing ignition module to shut down

 

flame across sensor rod.

 

2.

Improperventing,excessiveblockage,or

2.

Have vent system inspected, including

 

 

high wind conditions. Overdrafting of

 

the termination cap. Remove any restric-

 

 

straight (no offset) vertical vent systems

 

tion or obstruction. Add restrictor plate

 

 

over 15 feet in height.

 

modelVR-58 in straight vertical systems

 

 

 

 

over 15 feet (if not previously installed).

 

 

www.desatech.com

 

116035-01B

Page 34
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Desa (V) CD36R(N, (V) CD36T(N, P) installation manual Ment Parts