E18
Alpha
Freeze Protection / Low Temperature Fault
Display shows E18; unit may shut down during operation, especially in cold weather.
Advertisements
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.
Advertisements
Possible Causes
Failed freeze protection sensor, Inoperative circulation pump (if equipped), Inadequate insulation on piping, Control board freeze circuit failure
How to Fix / Troubleshooting
Safety: Turn OFF power and gas if there is any sign of frozen or burst piping. Do not attempt to operate a frozen heater.
- Inspect for freezing: Check the Alpha heater and nearby piping for frost, bulging, or leaks.
- Verify power: Freeze protection requires power. Ensure the unit has continuous power during cold weather.
- Check freeze sensor: Locate the freeze protection sensor on the heat exchanger or internal piping. Inspect wiring and connections.
- Thaw safely: If components are frozen but not burst, allow them to thaw slowly with ambient heat. Do not use open flames.
After thawing, have a technician inspect the Alpha heater for damage and test the freeze protection system.
Advertisements
Repair Difficulty
Hard
4/5
Required Part
Freeze Protection Sensor
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements