Troubleshooting - Desa VC42NE SERIES Owner's Operation And Installation Manual

CLEANING AND
MAINTENANCE
Continued
VENTING SYSTEM
Conduct annual inspection of the venting system
following these guidelines:
1. Check areas of venting system that are exposed
to the weather for corrosion (rust spots or streaks
and, in extreme cases, holes). Have these items
replaced immediately by a qualified service
person.
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: All troubleshooting items are listed in order of operation.
OBSERVED PROBLEM
Ignitor will not spark or pilot
will not light
116237-01E

TROUbLEShOOTING

POSSIBLE CAUSE
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 igni-
tion module or power trans-
former is bad
www.desatech.com
2. Remove the vent cap and shine a flashlight
into the vent. Remove any foreign material.
3. Check for evidence of excessive condensation.
Continuous condensation can cause corrosion
of caps, pipes and fittings and can be caused
by having excessive lateral runs, too many
elbows or exterior portions of the system being
exposed to cold weather.
4. Inspect joints to verify that no pipe section or
fitting has been disturbed and loosened. Check
mechanical supports such as wall straps for
rigidity.
REMEDY
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 repeated
attempts appliance does not
light, call for qualified service
and repair
3. Remove debris and dirt, in-
spect and clean any other
possible obstructions
4. Contact your gas supplier to
check pressure
5. Have a qualified technician
replace pilot line
6. Replace control valve (Refer to
Replacement Parts, page 34)
7. Check that main power is
on and that all wire connec-
tions are made correctly to
the ignition model (see Wiring
Diagram, page 27). 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
transformer replaced
31