Troubleshooting Guide - Nortec GH Series Installation, User & Maintenance Manual

Symptom
On-off Switch Energized, Humidistat calling for
operation. Unit does not operate.
Unit energized/Ignition module okay. Blower
NOT running.
Power to unit on, humidistat on, indicator lights
on except humidity demand.
Pressure switch input okay but no trial for
ignition after purge delay.
Valve activates. No ignition. LED displays 3
flashes.
Igniter on. No valve operation. LED displays 3
flashes
Valve activates. Ignition occurs, LED displays 3
flashes.
Flame with no call for heat.

TROUBLESHOOTING GUIDE

- No power to appliance. Check circuit breaker. Check disconnect switch.
- Defective Transformer. Check secondary voltage. If no 24 volts, replace
transformer if breaker is not blown.
- Check re-setable stack high limit switch and reset if necessary.
- Low voltage breaker blown. Check breaker (located on bottom of interface
panel). If breaker blown, reset breaker.
- Fault LED not operating. Loose connection at ignition module. Defective
LED. Check wiring connections. Check for continuity between FC1 And
FC2 on ignition control module using multimeter.
- Ignition module locked out. Check LED diagnostic light MC display for
failure identification. See Fault Conditions for identification of fault codes.
- Loose wire(s). Check wiring connection(s).
- No call for humidity.
- Defective or loose blower driver board. Check blower driver board for green
LED. Check if properly seated. Replace if properly seated but no LED.
- Defective blower. Replace blower.
- 24VDC power supply defective or fuse blown. Check fuse on power supply.
- Control signal miswired. Check signal.
- Low water level. Check water supply.
- Low float switch stuck or defective. Check continuity of float switch and
inspect floats. Clean floats if scaled up; replace if defective.
- Bad control. Check LED for steady on or check MC display.
- Miswired. Check PSW terminal voltage.
- Check for change of state when unit is turned down.
- Bad control. Check LED for steady on.
- Defective hot surface ignitor. Check resistance (see service checks).
- No gas supply, turn on gas.
- Mis-wired ignitor. Check wiring.
- Bad control. Replace.
- Valve wiring not connected. Connect.
- Damaged valve coil. Replace valve.
- Bad control. Check voltage between MV1 & ground. Replace control.
- Defective flame sensor. Check flame current (see service checks).
- S2 wire not connected or loose. Connect.
- L1 and neutral wires to unit reversed. Correct polarity.
- Stuck valve. Shut off gas supply. Check LED for 2 flashes. Replace valve.
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Causes / Service Checks