John Wood Atmospheric Gas (Standard) - Manual (Page 33)

33
STATUS LIGHT AND DIAGNOSTIC CODE TROUBLESHOOTING CHART (Continued)
LED STATUS PROBLEM CORRECTIVE ACTION
4 FLASHES The Gas Control Valve’s
temperature sensor has detected
that the water temperature was
too high. Once this condition
occurs, the Main Burner and
the Pilot Light will be shut off.
Since the Pilot light will be off,
should this condition occur, this
Flash Code will only be displayed
immediately after the Pilot has
been relit. Turn Gas Control Valve/
Thermostat knob to OFF. Relight pilot and verify 4 flashes. If 4 flashes are
observed, turn Gas Control Valve/Thermostat knob
to OFF. Turn Main Gas Supply OFF. Replace the
Gas Control Valve/Thermostat. See “Removing and
Replacing the Gas Control Valve/Thermostat.”
5 FLASHES The temperature sensor
(thermistor) is defective. Turn Gas Control Valve/Thermostat knob to OFF.
Replace Gas Control Valve/Thermostat. See
“Removing and Replacing the Gas Control Valve/
Thermostat.”
7 FLASHES Gas Control Valve failure. Turn Gas Control Valve/Thermostat knob to OFF. Turn
Main Gas Supply OFF. Replace the Gas Control Valve/
Thermostat. See “Removing and Replacing the Gas
Control Valve/Thermostat.”
8 FLASHES This condition only appears if the
gas control/temperature knob has
been turned off and the thermopile
continued to produce electric
power. This condition can occur
if the thermopile does not cool
down as quickly as expected when
the unit is shut off. This condition
can also occur if the gas control/
temperature knob has been turned
off and the pilot continues to
operate because the pilot valve is
stuck in the open position. Make sure that the gas control valve/thermostat knob is
set to OFF. Wait one minute. Remove the outer door.
Look through the sight glass for a pilot flame. If a pilot
flame is observed with the gas control valve/thermostat
knob set to the OFF position, the pilot valve is stuck open.
Turn the main gas supply OFF. Replace the gas control
valve/thermostat. For instructions, see “Removing and
Replacing the Gas Control Valve/Thermostat.”
If the pilot flame is not observed when the gas control
valve/thermostat knob is set to the OFF position, wait 10
minutes for the thermopile to cool, then attempt to relight
the pilot by following the lighting instructions on the water
heater’s label. If this condition returns, replace the gas
control valve/thermostat. See “Removing and Replacing
the Gas Control Valve/Thermostat” for instructions.