HVACopediaICP · Heat pump
Red TRIP LED Comfort Alert TRIP - Y1 call but compressor not running
What the control is telling you
Thermostat Y1 demand is present at the module but the compressor is not running.
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
- Compressor internal protector open
- Outdoor disconnect open
- Compressor breaker or fuses open
- Broken wire or bad connector
- Low pressure switch open (if fitted)
- Contactor failed open
Test and repair steps
- Warning: Turn off power at the disconnect before checking wiring or contactor.
- Check line voltage at the disconnect, breaker and fuses.
- Check the contactor pulls in with 24 V on the coil and the contacts close.
- Check wiring and connectors to the compressor.
- If the compressor is hot, let the internal protector reset.
- Check the low pressure switch if fitted.
Settings for these units
Outdoor unit clearances · ICP N4H3 Heat Pump
| Location | Minimum |
|---|---|
| Above unit (discharge) | 48 in. (1.2 m) |
| Each coil side (intake) | 18 in. (457 mm) |
| One coil side, reduced (unit to structure) | 6 in. (152 mm) |
| Control box corner and service panel | 24 in. (610 mm) |
| Between side-by-side units | 18 in. (457 mm) |
| Roof overhang above unit (with gutters) | 48 in. (1.2 m) vertical |
Small objects (post, fence end): clearance about equal to the object width.
Do not install under an overhang without gutters.
Models that show this code
1 model in ICP N4H3 Heat Pump
Other codes on the same units
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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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