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107050
OWNER’S MANUAL
TROUBLESHOOTING
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
Ignitor will not spark or pilot will not light
Pilot lights but will not stay lit
No gas to main burner, although wall switch
and valve are set to the ON position
Frequent main burner outage
POSSIBLE CAUSE
1. No gas supply, or equipment 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 knob is not opening
7. No power to unit or the ignition module
or power transformer is bad
1. Loose wiring on ignitor wire to ignition
module and/or poor ground to ignition
module
2. Pilot flame too low to sense
1. Wall switch wires defective or too long
2. Sensor, valve, or ignition module is not
operating
1. Pilot flame may be too low, causing
safety pilot to “drop out”
2. Vent may be blocked or restricted
REMEDY
1. Check to see if you have gas supply and
that the 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, inspect and
clean any other possible obstructions
4. Contact your gas supplier to check pres-
sure
5. Have a qualified technician replace pi-
lot line
6. Replace control valve (Refer to Replace-
ment Parts, page 17)
7. Check that main power is on and that all
wire connections are made correctly to
the ignition model (see Wiring Diagram,
page 14). Check for 24 VAC at the sec-
ondary side of the transformer. If 24 VAC
is present and the module does not op-
erate, have the module replaced other-
wise have the transformer replaced
1. Check ignitor wire connection. Refer to
wiring diagram (see Wiring Diagram,
page 14) and/or check ground wire to
ignition 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. Check electrical connections
2. Recheck problems 1 and 2
1. Clean and adjust pilot flame for maximum
flame impingement on sensor
2. Have vent inspected for blockage or
damage
Note:
For additional help, visit DESA
International’s technical service web
site at
www.desatech.com
.
www.desatech.com
Note:
Before troubleshooting the system,
make sure the equipment shutoff valve is ON.
Continued