Furnace LED shows code 45; furnace may lock out and require power reset.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Turn off power at the breaker before handling the control board.
Steps:
- Power cycle: Turn off power for at least 60 seconds, then restore. Observe if the code returns immediately.
- Check line voltage quality: Measure supply voltage to ensure it is within Keeprite specifications (typically 120VAC ±10%).
- Inspect board: Look for burnt traces, swollen components, or moisture damage on the control board.
If code 45 persists and no external wiring or component issues are found, the control board should be replaced with the correct Keeprite OEM part by a technician.
Repair Difficulty
Required Part
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