John Wood Atmospheric Gas (Standard) - Manual (Page 31)

31
PILOT LIGHT TROUBLESHOOTING FLOWCHART
Have you bled all the air
from the pilot tube and
gas supply line?
NO
While repeatedly depressing the igniter
button, push in and hold the gas control/
temperature knob until the pilot is lit and
maintains a stable flame (status light will
blink). It may take up to 90 seconds of
pilot operation before status light blinks.
Once status light blinks, release the gas
control/temperature knob.
Section A: Pilot light will not light (new installation).
Is the manual gas shut-off valve,
located in the supply line to the
water heater, in the on position?
NO
YES
Turn the manual gas shut-off valve to
the on position and follow the lighting
instructions on the front of the water heater.
Is the igniter producing a
spark?
YES
NO
Follow the “Testing the Igniter
System” section in this manual.
Check for insufficient combustion air.
Are the combustion air supply and ventilation openings
of sufficient size? See “Combustion Air Supply and
Ventilation” section in this manual for requirements.
Does the return air duct for the furnace/
air handler/air conditioner draw its air from
the same location as the water heater?
See the “Location Requirements” section
and the “Combustion Air Supply” section. Is there proper
drafting at the
drafthood? See
“Checking the Draft”
section in this manual.
Contact a Heating and Air
Conditioning service technician
to relocate the return air duct.
The water heater’s pilot can be
extinguished when the heating
or cooling system is turned on
if the return air duct is in the
same location.
Correct size of
openings to allow
sufficient air.
NO
YES
YES
NO
Section C: Pilot light will not remain lit.
Complete this section after completing Section B.
YES
Set thermostat to desired temperature.
Section B: Pilot light repeatedly goes out.
Check the Base-Ring Filter and
Flame Arrestor for blockage due
to lint or dust. Are both the Air
Filter and Flame Arrestor clean? Refer to the “Maintenance of
your Water Heater” section of this
manual for information on cleaning
the flame arrestor and burner.
NO
YES
Does the diagnostic status light on the
gas control valve/thermostat give
a two flash error code?
Does the flame
arrestor show signs
of discoloration?
YES
Shut-off the gas supply to the water heater at the
manual gas shut-off valve. Use the number on the
cover of this manual to contact Customer Service.
NO
Reassemble the heater, press the thermal
switch, and attempt to return the heater to
service. Does the pilot remain lit?
YES
Set to desired temperature.
NO
YES
Refer to the “Replacing the Pilot
Assembly” instructions in the manual.
Reassemble and restore to service.
Go to section C.
NO
NOTE: If you are still experiencing diffi culties after following
the steps in sections A, B, and C, please use the number
on the cover of this manual to contact Customer Service.
Check the vent system for
restrictions/obstructions and
check the vent termination
height. Refer to the “Installation
Instructions” section of this
manual for specific requirements.
THERMAL
SWITCH
THERMAL SWITCH LOCATION
FIGURE 29.
YES
If you are still having difficulty keeping the pilot
lit, reference the number on the cover of this
manual for service information.
NO
YES