A.O. Smith Water Heater - Manual (Page 31)

PILOT LIGHT TROUBLESHOOTING FLOWCHART
Does pilot light go out when
button is released?
■NO^
YES
Check Draft. (See Checking the
Draft section of this manual.)
Has the thermal switch
tripped?
YES
■NO^
Are the wires from the gas
control valve/thermostat firmly
connected to the switch?
YES
Are the wires damaged
and/or frayed?
■NO^
Secure connections
and attempt a relight.
■NO^ Is the thermocouple
connection loose?
Replace the gas control
valve/thermostat.
Check for insufficient
combustion air.
YES YES
1
L
[Tighten the connection |
Test the thermocouple using the following
procedure: Disconnect the thermocouple from the
gas control valve/thermostat. Using a multimeter
with alligator clip leads, attach the red lead to
the body (copper part) of the thermocouple.
Attach the black lead to the end (silver part) of
the thermocouple that connects to the gas control
. valve/thermostat. Follow the instruction to light
■NO the pilot and watch the voltage readings on the
multimeter. After 45 seconds the meter should
read 12 millivolts DC or more.
■YES ^Does the thermocouple pass the test? ^NO
Are there openings
for make-up air to
enter the room?
■NO^
Install correct size make-up air openings per
the Combustion Air Supply and Ventilation
section in this manual.
YES
J*L
Are the openings of sufficient size?
See Combustion Air Supply and Ventilation
section in this manual for requirements. ■NO^
Correct size of openings to
allow sufficient air.
YES
Is there a furnace/air
■NO ■ handler in the same room as
the water heater?
YES
Does the return air duct for the furnace/air handier
draw its air from a separate location than the water
heater? See the Location Requirements section and the
Combustion Air Supply section.
■NO^
Contact a local Heating, Ventilation, Air­
Conditioning & Refrigeration authorized
service provider.
YES
Is there proper drafting at the
' draft hood? See Checking the
Draft section in this manual.
■NO^
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.
YES
J*L
Is the flame-arrestor free from
debris due to excessive lint, dirt,
dust or oil? ■NO^
Refer to the Use & Care Guide section of this manual for
information on cleaning the flame-arrestor.
YES
Check the water heater for a Flammable Vapor (FV) event. Note: it may be
necessary to remove the manifold door assembly to visually inspect the water
heater. Reference the Maintenance of your Water Heater section of this manual
for removal instructions.
Is the igniter wire insulation burnt or
show signs of discoloration?
■NO^
Is the pilot tube
damaged?
■NO^
YES YES
Does the flame-
arrestor show signs
of discoloration and/
or debris?
Shut-off the gas supply to the water
heater at the manual gas shut-off valve,
then contact Residential Technical
Assistance by referencing the phone
number on the front of the water heater.
YES
U
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