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100221773_2000189439_Rev. 01
PROBLEM
POSSIBLE CAUSE(S)
CORRECTIVE ACTION
BLOWER RUNS
CONTINUOUSLY
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. 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
HOT SURFACE IGNITER
NOT GLOWING
FOLLOWING WARM-UP
PERIOD
1. 120VAC polarity reversed at 120VAC
outlet receptacle
2. Defective hot surface igniter
3. Defective gas control valve/thermostat
1. Reverse polarity at 120VAC outlet
receptacle
2. Replace igniter
3. Replace gas control valve/thermostat
VENT PIPE TOO HOT
1. Blower high limit switch fails to open -
switch defective
2. Not enough dilution air to mix with flue
gases
3. Air in room too hot for mixing with flue
gases
4. Wrong burner orifice
5. Wrong or missing vent termination
screen
1. Replace blower high limit switch
Replace blower high limit switch
2. Proper air circulation must be provided
for combustion and dilution of flue
temp
3. Increase ventilation to lower room
temperature
4. Install correct orifice
5. Install and secure proper vent
termination screen
RESETTING THE HEATER CONTROL
•
Soft lockouts as diagnosed by the system error codes require the gas control to be reset.
•
To reset the control, slide the “ON/OFF” switch to the “OFF” position. Wait for 10 seconds and move the switch back
to the “ON” position.
•
If the problem that caused the control to lock out has not been corrected, the control will remain or again go back
into lockout.
LOCKOUTS
Soft Lockout
•
occurs when a system safety device trips to break the sequence of operation. The control will retry the system in a
timed basis but will not reinstate operation until the failure is corrected.
Hard Lockout
•
occurs when the main controller fails and must be replaced.
The gas control valve\thermostat includes a temperature limiting ECO (Energy Cut Off) system that will shut off the water
heater if the water temperature is too high.
Should the water temperature get too high, the diagnostic status light will indicate a code (4 flashes), indicating an over-
temperature condition and the main burner will be shut off. If a high temperature condition occurs, turn the main gas
supply OFF and have the water heater repaired by a qualified service technician. Contact your local dealer for service
information.
Note:
Should an over-temperature condition occur, restart the water heater and verify the LED flash sequence. If the
4 flash sequence is observed, slide the “ON/OFF” switch to the “OFF” position. Turn Main Gas Supply “OFF”. Replace
the gas control valve\thermostat.
