Desa (V) CD36R(N - Manual (Page 34)

34
www.desatech.com 116035-01B
TROUBLESHOOTING
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
let cool before servicing. Only a quali-
fied service person should service
and repair heater.
CAUTION Never use a wire,
needle, or similar object to
clean pilot. This can damage
pilot unit.
OBSERVED PROBLEM POSSIBLE CAUSE REMEDY
Ignitor will not spark or pilot will not light
Pilot will not stay lit
Frequent outage of main burner and pilot
after complete ignition sequence.
1. No gas supply, or shutoff valve is OFF
2. Air in gas line
3. Construction debris clogging pilot orifice
4. Low gas pressure
5. Kinked pilot line
6. Control valve is not opening
7. No power to unit or the ignition module
1. Loose wiring on ignitor wire to ignition
module and/or poor ground to ignition
module
2. Pilot flame too low to sense
1. Pilot flame may be too low to sense flame
causing ignition module to shut down
2. Improper venting, excessive blockage, or
high wind conditions. Overdrafting of
straight (no offset) vertical vent systems
over 15 feet in height.
1. Check to see if you have gas supply and
that equipment shutoff valve is opened
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. Remove debris and dirt, and inspect and
clean any other possible obstructions
4. Contact your gas supplier to check
pressure
5. Have a qualified technician replace pi-
lot line
6. Replace control valve (Refer to Replace-
ment Parts, page 36)
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.
1. Check wiring connection. Refer to wir-
ing diagram (see Wiring Diagram, page
19) and/or check ground wire to igni-
tion module
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
1. Clean and adjust pilot flame for maximum
flame across sensor rod.
2. Have vent system inspected, including
the termination cap. Remove any restric-
tion or obstruction. Add restrictor plate
model VR-58 in straight vertical systems
over 15 feet (if not previously installed).
Electronic Ignition System
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