Desa (V) CB36(N, Owner'S Operation And Installation Manual

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www.desatech.com
117437-01
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-
fi ed 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 orifi ce
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 fl ame too low to sense
1. Pilot fl ame may be too low to sense fl ame
causing ignition module to shut down
2. Improper or restricted venting.
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 qualifi ed 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 qualifi ed technician replace pi-
lot
line
6. Replace control valve (Refer to Replace-
ment Parts , page 26)
7. Check that main power is on and that
wire connections are made correctly to
the ignition model (see Wiring Diagram ,
page 20). 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
9) 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 qualifi ed technician replace
pilot assembly if broken or corroded
1. Clean and adjust pilot fl ame for maximum
fl ame across sensor rod.
2. Locate and correct all vent conditions
(see
Checking for Proper Venting, page 8)
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 fi lter