Desa (V)CB36N(E) - Manual (Page 28)

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TROUBLEShOOTING
Continued
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
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 or restricted venting
OBSERVED PROBLEM
Electronic Ignition Models Only
Ignitor will not spark or pilot will
not light
Electronic Ignition Models Only
Pilot will not stay lit
Electronic Ignition Models Only
Frequent outage of main burner
and pilot after complete ignition
sequence
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, and
inspect 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 wire connections are
made correctly to the ignition
model (see Wiring Diagrams,
page 13). 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
1. Check wiring connection. Refer
to wiring diagram (see Wiring
Diagrams, page 13) 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. Clean and adjust pilot flame
for maximum flame across
sensor rod
2. Locate and correct all vent
conditions (see Checking for
Proper Venting, page 10)