Sterling QVES - Manual (Page 27)

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7. Defective thermocouple
(Standing pilot units only).
8. Drafts around unit.
9. Pilot valve not opening (faulty
wiring).
10. No spark (if applicable) (faulty
wiring).
11. Defective gas valve.
1. Loose
wiring.
2. Defective motor overload protector or
defective motor.
3. Defective power venter relay.
1. Fan relay heater element improperly
wired.
2. Defective venter relay switch.
3. Motor overload protector cycling on
and off.
4. Motor not properly oiled.
1. Improperly wired venter relay.
2. Main burners not lighting while
thermostat calls for heat.
3. Defective venter relay.
1. Incorrect gas input.
2. Heater
undersized.
3. Thermostat malfunction.
4. Heater cycling on limit control.
5. Check outside dampers if used.
7. Check thermocouple connection,
and replace if defective.
8. Eliminate drafts. Refer to
"Installation".
9. Inspect and correct all wiring.
10. Inspect and correct ignition system
wiring. See symptoms W, X,& Y.
11. Replace.
1. Check and tighten all wiring connec-
tions per diagrams. Thermostat wires
tagged "W" and "G" must be
connected together (unless special
thermostats are used; if so, see
thermostat wiring diagram). See
electrical connections.
2. Replace motor.
3. Check for 24V across 1 and 3
terminals on fan relay. If 24V is
present, jumper terminals numbered
2 and 4. If motor runs, the relay
is defective and must be replaced.If
24V is not present, check wiring per
diagrams.
1. Be sure venter relay heater terminals
are connected per diagrams.
2. Replace venter relay.
3. Check motor amps against motor
name plate rating, check voltage,
replace power venter motor if defective.
4. Refer to label on motor.
1. Check all wiring.
2. Refer to H & N symptoms.
3. Replace venter relay.
1. Refer to "Operation".
2. This is especially true when the heated
space is enlarged. Have the heat loss
calculated and compare to the heater
output (80% of input). Your gas
supplier or installer can furnish this
information. If heater is undersized,
add additional heaters.
3. Replace thermostat.
4. Check air movement through heat
exchanger. Check voltage to fan
motor. Clean power venter blade and
heat exchanger and oil power venter
motor.
5. Adjust dampers accordingly.
Troubleshooting Guide
SYMPTOMS POSSIBLE CAUSE(S) CORRECTIVE ACTION
N. Pilot will not light or will not
stay lit. continued
O. Power venter will not run.
P. Power venter motor turns on
and off while burner is
operating.
Q. Power Venter motor will not
stop.
R. Not enough heat.