User Guide

36 RH180 Manual
Code Denion Remedy
14 Check for restricons in air ow 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 posion.
Check for foreign materials in combuson chamber and/or exhaust piping.
Check heat exchanger for cracks and/or separaons.
Check heat exchanger surface for hot spots which indicate blockage due to scale
build-up. Refer to instrucons in manual for ushing heat exchanger.
Measure resistance of safety circuit.
Ensure high re and low re manifold pressure is correct.
Check for improper conversion of product.
16 Over Temperature
Warning (safety
shutdown because unit
is too hot)
Check for restricons in air ow around unit and vent terminal.
licensed
professional only
Check for foreign materials in combuson 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 posioned on the tank surface.
Replace sensor.
38 CO or FV Sensor Check sensor wiring for damage.
Measure resistance of sensor.
Replace sensor.
52 Modulang Solenoid
Valve Signal
Check modulang gas solenoid valve wiring harness for loose or damaged terminals.
Measure resistance of valve coil.
61 Combuson Fan Ensure fan will turn freely.
Check wiring harness to motor for damaged and/or loose connecons.
Measure resistance of motor winding.
63 Circulaon ow rate
has dropped below 1.3
gpm
Check water lter for blockage
Check pump operaon 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 connecons.
Measure resistance of each solenoid valve coil.
72 Flame Sensing Device Verify ame rod is touching ame when unit res.
Check all wiring to ame rod.
Remove ame rod and check for carbon build-up; clean with sand paper.
Check inside burner chamber for any foreign material blocking ame at ame rod.
Measure micro amp output of sensor circuit with ame present.
Replace ame 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
Conrm the water heater is plugged in and 120 volts is available