Gas Input Rate
34
GKNE-SVX001B-EN
No Cycling or appliance power or thermostat call for heat
since appliance failure has occurred.
1. Check the system thermostat to make sure it is calling
for heat. (Do not cycle the thermostat on and off at this
time.)
2. Remove the appliance burner compartment door. Do
not interrupt power to the control board by opening
any electrically interlocked panels.
3. Observe the LED indicator on the control board (a
greem LED labeled “OK” indicates system faults);
check and repair system as noted in the chart to the
right.
R. High limit is tripping.
1. Unit is over fired.
2. Air flow is too low.
3. Defective high limit.
4. Defective control board.
1. Refer to "Gas Input Rate." Check orifice size.
Replace if too large.
2. Check for proper voltage; ensure blower
assembly is correct.
3. Check operation of switch. If switch is open
during operation, check gas pressure and/or
CFM; adjust accordingly. If switch is open
during start- up, replace switch.
4. Check for 24V on line side of high limit. Constant
voltage should be recorded. If not, control
board is suspect. Check flash code.
S. Power ventor will not run.
1. No power supply to unit.
2. Thermostat not calling.
3. Loose wiring or connection.
4. Motor overload protection is tripping or bad
motor.
5. Defective control board.
1. Turn on power supply, check fuses and replace
if bad.
2. Turn up thermostat. Check for 24V on terminals
R and W1 on terminal strip.
3. Check all wiring in the power vent circuit to
ensure good connection, including "Neutral."
4. Check for 115V between motor leads and check
amp draw of motor. Replace if necessary.
5. Check for continuous 115V on terminal "CBM"
Blower" and neutral during call for heat. If not
present and all checks are normal, replace.
T. Power ventor turns on and off during
operation.
1. Power ventor improperly wired.
2. Motor overload cycling or defective motor.
3. Defective control board.
1. Check power ventor circuit per wiring diagram.
2. Check motor voltage and amp draw to motor
name plate, replace if motor found defective.
3. Check for continuous 115V on terminal "CBM"
Blower" and neutral during call for heat. If not
present and all checks are normal, replace.
U. Power ventor will not stop.
1. Power ventor improperly wired.
2. Main burner did not light on call for heat.
3. Defective control board.
1. Check power ventor circuit per wiring diagram.
2. Heater is in lockout mode; check flash code
table for problem.
3. If no flash codes present along with no call for
heat, replace control board.
V. Noisy power ventor.
1. Power ventor wheel loose.
2. Power ventor wheel is dirty.
3. Power ventor wheel is rubbing on housing.
1. Replace or tighten.
2. Clean power ventor wheel.
3. Realign power ventor wheel.
Table 12. Separated combustion tubular blower troubleshooting guide (continued)
SYMPTOMS
POSSIBLE CAUSE(S)
CORRECTIVE ACTION
WARNING
Line voltage power can cause product damage, severe
injury or death. Only a trained experienced service
technician should perform this trouble-shooting.
NOTICE
Air flow proving switch and power ventor hose barbs
must be free of any dust or debris at all times.
Periodically check these openings and/or if any
problems occur.
Table 13. Separated combustion tubular blower troubleshooting with LED indicator assistance
LED STATUS
INDICATES
CHECK/REPAIR
Slow Flash
Control OK, no call for heat.
Not Applicable
Fast Flash
Control OK, call for heat present.
Not Applicable
