Diagnostic Codes And Remedies - Giant Factories ANSI Z21.10.3 Owner's Manual

TROUBLESHOOTING GUIDE

Diagnostic Codes and Remedies

Code Definition
19
Electrical Grounding
25
Condensate Trap is full
31
Burner Sensor
Outgoing Water
32
Temperature Sensor
Heat Exchanger Outgoing
33
Temperature Sensor
Outside Temperature
41
Sensor
Inlet Water Temperature
51
Sensor
Modulating Solenoid Valve
52
Signal
57
Burner
Secondary heat
58
exchanger
61
Combustion Fan
65 Water Flow Control
70
PC Board
71
Solenoid Valve Circuit
72
Flame Sensing Device
73
Burner Sensor Circuit
79
Water Leakage Detected
Scale Build-up in Heat
LC #
Exchanger (when checking
(LC0,
maintenance code history,
LC1,
"00" is substituted for
LC2,...)
"LC")
Maintenance has been
FF
performed
No
Nothing happens when
code water flow is activated.
Remedy
licensed
professional Check all components for electrical short.
only
Check condensate trap and drain line for blockage.
Replace condensate trap.
Measure resistance of sensor. Replace sensor.
Check sensor wiring for damage.
Measure resistance of sensor.
Clean sensor of scale build-up.
Replace sensor.
Check modulating gas solenoid valve wiring harness for loose or damaged terminals.
Measure resistance of valve coil.
Contact a licensed professional.
There is scale build-up in the secondary heat exchanger and it needs to be flushed to prevent damage.
Refer to the flushing instructions in the manual.
Hard water must be treated to prevent scale build-up or damage to the heat exchanger.
licensed
Ensure fan will turn freely.
professional
Check wiring harness to motor for damaged and/or loose connections.
only
Measure resistance of motor winding.
The water flow control valve has failed to close during the bath fill function.
Immediately turn off the water and discontinue the bath fill function.
Contact a licensed professional to service the appliance.
Check PC board DIP switches for correct position.
Check the connection harness at the connection on the PC board.
Replace PC board.
Replace the PC Board.
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.
Check sensor wiring and PC board to be sure that they have not been damaged.
Replace sensor.
Turn off water supply and contact licensed professional.
LC0~LC9 indicates that there is scale build-up in the heat exchanger and that the heat exchanger needs to
be flushed to prevent damage.
Refer to the flushing instructions in the manual.
Hard water must be treated to prevent scale build-up or damage to the heat exchanger.
To operate the water heater temporarily until the heat exchanger can be flushed, push the On/ Off button
on the temperature controller five (5) times.
Repeated LC codes will eventually lock out the water heater.
Please call Giant technical department at 1-800-363-9354.
Indicates a licensed professional performed maintenance or corrected an issue.
Clean inlet water supply filter.
On new installations ensure hot and cold water lines are not reversed.
Verify you have at least the minimum flow rate required to fire unit.
Check for cold to hot cross over. Isolate circulating system, if present.
Turn off cold water to the unit, open pressure relief valve; if water continues to flow, there is bleed over in
licensed
your plumbing.
professional Verify if turbine spins freely.
only Measure the resistance of the water flow control sensor.
If the display is blank and clicking is coming from the unit, disconnect the water flow servo motor (GY,
BR, O, W, P, BL, R). If the display comes on, replace the water flow servo motor.
45