John Wood POWER VENTED GAS FIRED WATER HEATER Installation And Operating Instructions Manual page 33

PROBLEM
COMBUSTION ODOURS
SMOKING AND CARBON
FORMATION
UNABLE TO LIGHT
THE BURNER
SIZZLING, RUMBLING
NOISE
WATER LEAKAGE
BLOWER WILL
NOT START
BLOWER RUNS
CONTINUOUSLY
POSSIBLE CAUSE(S)
1. Air inlets blocked
2. Insuffi cient secondary air
3. Flue clogged
4. Heater installed in a confi ned area
5. House too tight
1. Air inlets blocked
2. Insuffi cient secondary air
3. Low gas pressure
4. Orifi ce too large
5. Flue clogged
6. defective gas control valve/thermostat
7. Heater installed in a confi ned area
1. Air in gas line
2. Pressure switch
3. Blocked exhaust
4. Wire connection
5. Defective gas control valve/thermostat
6. Defective igniter
1. Scale and sediment
2. Condensation dripping on burner
1. Condensation
2. Dripping Temperature & Pressure Relief
Valve
3. Thermostat does not shut-off
4. Drain valve dripping/leaking
5. Tank Leak
1. No power to unit
2. Thermostat set too low
3. Defective air pressure switch
4. Defective blower
5. Disconnected or loose wire
6. Control locked out
7. Incorrect polarity
1. Air pressure switch not closing due to
insufficient draft – check for:
a. Vent piping blocked
b. Piping length too long
c. Clogged/dirty blower
2. Disconnected, torn or blocked pressure
switch hose from air pressure switch to
blower housing
3. Defective pressure switch
4. High limit switch open due to excessive
vent temperature or defective switch
1. Unblock inlet air openins
2. Provide fresh air ventilation to the water
heater
3. Clean, locate source and correct
4. Provide fresh air ventilation to the water
heater
5. Provide fresh air ventilation to the water
heater
1. Unblock inlet air openings
2. Provide ventilation to water heater.
Check fl ue way, fl ue baffl e and burner
3. Check with gas utility company
4. Replace with correct orifi ce
5. Clean, locate source and correct
6. Replace gas control valve/thermostat
7. Provide fresh air ventilation
1. Purge the air from gas line
2. Check the pressure switch, make sure the
pressure switch hose is not kinked
3. Check vent pipe for blockage
4. Check wire connections
5. Replace the gas control valve/thermostat
6. Replace igniter
1. Drain/flush-provide water treatment if
needed
2. Refer to "Condensate" section
1. Refer to "Condensate" section
2. Refer to "Temperature & Pressure Relief
Valve" section
3. Check the Thermostat
4. Back fl ush to clean- out sediment, replace
if necessary.
5. Check "Leakage Checkpoints"
1. Plug in power cord, check fuses and/or
supply voltage
2. Turn temperature knob to higher setting
3. Replace air pressure switch
4. Replace blower
5. Repair and reconnect wires
6. Reset – determine cause of lockout
7. Repair polarity
1. Determine cause of insufficient draft.
Check draft with manometer at pressure
switch
a. Remove blockage
b. Reduce vent length/increase vent size
c. Clean blower wheel
2. Reconnect or replace pressure switch
hose
3. Replace defective pressure switch
4. Determine cause of overheating check
for: overfiring, insufficient air supply, high
ambient air temperature (once high limit
switch activated, must be replaced)
– 33 –
CORRECTIVE ACTION