36
Giant Manual
Code
Definition
Remedy
14
Check for restrictions in air flow around unit and vent terminal.
Thermal Fuse
licensed
professional only
Check gas type of unit and ensure it matches gas type being used.
Ensure dip switches are set to the proper position.
Check for foreign materials in combustion chamber and/or exhaust piping.
Check heat exchanger for cracks and/or separations.
Check heat exchanger surface for hot spots which indicate blockage due to scale
build-up. Refer to instructions in manual for flushing heat exchanger.
Measure resistance of safety circuit.
Ensure high fire and low fire manifold pressure is correct.
Check for improper conversion of product.
16
Over Temperature
Warning (safety
shutdown because unit
is too hot)
Check for restrictions in air flow around unit and vent terminal.
licensed
professional only
Check for foreign materials in combustion chamber and/or exhaust piping.
Check for clogged heat exchanger.
Check that the gas type being used it correct for your unit.
30
FV Sensor
Check sensor wiring for damage.
Measure resistance of sensor.
Replace sensor
31
Burner Sensor
32
Heat Exchanger
Outgoing Temperature
Sensor
Check sensor wiring for damage.
Measure resistance of sensor.
Clean sensor of scale build-up.
Replace sensor.
35
Tank Temperature
Sensor
Check sensor wiring for damage.
Measure resistance of sensor.
Verify that sensor is properly positioned on the tank surface.
Replace sensor.
38
CO or FV Sensor
Check sensor wiring for damage.
Measure resistance of sensor.
Replace sensor.
52
Modulating Solenoid
Valve Signal
Check modulating gas solenoid valve wiring harness for loose or damaged terminals.
Measure resistance of valve coil.
61
Combustion Fan
Ensure fan will turn freely.
Check wiring harness to motor for damaged and/or loose connections.
Measure resistance of motor winding.
63
Circulation flow rate
has dropped below 1.3
gpm
Check water filter for blockage
Check pump operation and wiring
Clean Heat Exchanger
71
SV0, SV1, SV2, SV3
Solenoid Valve Circuit
Fault
Check wiring harness to all solenoids for damage and/or loose connections.
Measure resistance of each solenoid valve coil.
72
Flame Sensing Device
Verify flame rod is touching flame when unit fires.
Check all wiring to flame rod.
Remove flame rod and check for carbon build-up; clean with sand paper.
Check inside burner chamber for any foreign material blocking flame at flame rod.
Measure micro amp output of sensor circuit with flame present.
Replace flame rod.
73
Burner Sensor Circuit
Check sensor wiring and PCB for damage.
Replace sensor.
No
code
No hot water, no light
or error code on the
display
Confirm the water heater is plugged in and 120 volts is available
