Installation Sheet
50 Page
Troubleshoong
Owner's Guide
Remote
Green
LED
Malfunction
description
Diagnosis
391
Two Times Air-fuelRatioRod
failure
• Check for connection/breakage of wires (Part #709)
and/orsootontheAFRrod.(Part#108)
441
Two Times Flow Sensor Failure
(Easy-Link System only)
• Check for connection/breakage of wires and/or
debris on the flow sensor impeller. (Part #402)
510
Six Times Abnormal Main Gas
Valve
• Check for connection/breakage of wires (Part #708)
and/or burn marks on the computer board (Part #701).
551
Six Times Abnormal Gas
SolenoidValve
• Check for connection/breakage of wires (Part #708)
and/or burn marks on the computer board (Part #701).
611
Four Times Fan Motor Fault • Check for connection/breakage of wires, dust buildup
in the fan motor (Part #103) and/or burn marks on
the computer board (Part #701).
• Check for frozen/corrosion of connectors (Part #103).
651
Four Times Flow Adjustment
ValveFault(Easy-
Link System only)
• Inspect the flow adjustment valve (Part #402), for
connection/breakage of wires, locked motor drive
due to scale buildup, and/or water leakage.
661
Four Times Bypass valve Fault
(540 (T-H3)
models only)
• Inspect the bypass valve (Part #403), for connection/
breakage of wires, locked motor drive due to scale
buildup, and/or water leakage.
701
711
One Time Computer board
Fault
• Check for connection/breakage of wires (Part #714).
721
Six Times False Flame
Detection
• For indoor models, check if condensate drain is
installed on the vent collar of the water heater.
• Check if there is leaking from heat exchanger (Part #401).
741
N/A Miscommunication
between water
heater and remote
controller
• Check the model type of the remote controller.
• Inspect the connections between the water heater
and remote controller.
• Check the power supply of the water heater.
751
N/A Miscommunication
between water
heater and
temperature
controller (Direct
vent Indoor models
only)
• Inspect the connections between the water heater
and temperature controller.
• Check the power supply of the water heater.
761
N/A Miscommunication
in Easy-Link system
• Check if the connections between the parent unit
andthechildunitsarecorrect.Refertopg.29-32.
941
Five Times Abnormal exhaust
temperature (Direct
vent Indoor models
only)
• Check if the set temperature is higher than 140°F
(60°C)andthesystemisRecirculation.
991
Five Times Imperfect
combustion
• Check the gas type of the water heater.
• Inspect the environment around the water heater.
Determine how long the unit has been installed.
• Check the altitude/elevation of the area of where
the water heater installed.
• Check if there is any blockage in the intake air and/
or exhaust.
• If the water heater is installed as a direct-vent system,
check whether there is enough distance between the
intake air terminal and the exhaust terminal.
• Check if there is grease and/or dirt in the burner (Part
#101) and the fan motor (Part #103), especially if the
water heater has been installed in a contaminated area.