HVACopediaICP · Heat pump
TRIP + ALERT flashing together Control voltage too low
What the control is telling you
TRIP and ALERT LEDs flashing at the same time mean the control voltage is too low for the module to operate.
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
- Transformer overloaded
- Low line voltage
Test and repair steps
- Measure 24 VAC at R-C of the module.
- Check transformer load; see Flash Code 9.
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.
Homeowner looking at this code? See what it means for you and when to call a technician.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.