Troubleshooting - A.O. Smith RESIDENTIAL GAS WATER HEATER Instruction Manual

TROUBLESHOOTING GUIDELINES TROUBLESHOOTING GUIDELINES
PROBLEM
NOT ENOUGH HOT WATER
VENT PIPE TOO HOT (ABOVE 170° F [ 77° C ] )
YELLOW FLAME
CONDENSATION
WATER LEAKS
LEAKING T & P
HOT WATER ODORS
(refer to cathodic protection)
WATER TOO HOT
WATER HEATER SOUNDS
SIZZLING - RUMBLING
SOOTING
BURNER WILL NOT STAY LIT –
GOES OUT 4-5 SECONDS
VENT GAS ODORS
These guidelines should be utilized by a qualified service agent.
CAUSE
1.) Blower will not run.
a. "ON/OFF" control switch turned off.
b. Blower unplugged.
c. No power at outlet.
d. Thermostat defective.
e. Control harness defective.
f. High limit control circuit open.
g. Blower motor defective.
2.) Thermostat problems
a. Thermostat set too low.
b. Thermostat or ECO defective.
3.) Others
a. Heater undersized.
b. Low gas pressure.
c. Incoming water is usually cold.
d. Leaking hot water pipes of fixtures.
e. Heater not lit or thermostat not on.
Wrong burner orifice.
Dirt in burner ports.
Combustion air path restricted.
Water on the floor under heater.
Water dripping from blower assembly.
Improperly sealed, hot or cold supply
connections, relief valve, drain valve or
thermostat threads.
Leakage from other appliances or water lines.
Condensation of flue products.
Thermal expansion in closed water system.
Improperly sealed valve.
High sulfate or mineral content in water
supply.
Bacteria in water supply.
Thermostat set too high.
Condensation dripping on burner.
Sediment at bottom of heater tank.
Improper combustion.
Outlet polarity is reversed.
High ambient room temperature.
Combustion air path restricted.
Defective gas valve.
Lack of air supply.
Improperly installed vent piping.
Downdraft
Poor Combustion
Turn switch to the "ON" position.
Plug blower back into 115 VAC outlet.
Repair service to outlet.
Replace thermostat.
Replace control harness.
Replace thermostat.
Replace blower assembly.
Adjust temperature control higher.
Replace thermostat.
Reduce hot water use.
Contact dealer.
Allow more time for heater to reheat.
Have plumber check and repair leaks.
Refer to LIGHTING INSTRUCTIONS.
Install correct orifice.
Turn off heater and gas, clean burner head.
Check exhaust venting and air openings in
bottom base pan for obstructions or blockage.
See CONDENSATION section.
Provide drip "TEE" to catch condensation, see
Figure 1.
Check for leaks at all condensate points. See
Figure 1. Also see LEAK CHECKPOINTS
section.
Inspect other appliances near water heater.
Refer to CONDENSATION section.
Install thermal expansion tank (Do not plug
T&P valve).
Check relief valve for proper operation (Do
not plug T&P valve).
Drain and flush heater thoroughly then refill.
Chlorinate water supply.
Refer to TEMPERATURE REGULATION
section.
Refer to CONDENSATION above.
Clean sediment from tank. Refer to
DRAINING.
Refer to Air Requirements.
Test polarity and correct.
Contact a service agency to determine cause.
Check exhaust venting and air openings in
bottom base pan for obstructions or blockage.
Replace gas valve.
Shut off water heater immediately and contact
a service agency to determine cause.
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SOLUTION