HVACopediaICP · Heat pump
8 Welded contactor
What the control is telling you
Compressor runs all the time.
Applies to: ICP N4H3 R-410A split heat pump (manual 428 01 5103 02); Comfort Alert codes apply only to units factory-fitted with the Comfort Alert module
Likely causes
- Contactor welded closed
- Thermostat demand wire not connected to the module
Test and repair steps
- Warning: Turn off power at the disconnect - the compressor may run with no call.
- Check contactor contacts; replace if welded.
- Check the Y demand wire is connected to the Comfort Alert module.
Settings for these units
- Outdoor unit clearances · ICP N4H3 Heat Pump
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Source: ICP N4H3 Installation Instructions 428 01 5103 02, Comfort Alert Diagnostics Codes (Figure 18), p.20. Summarized in our own words; check the original manual for your model.
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