ICP · Heat pump

6 Open start circuit

High severity ICP N4H3 Heat Pump

What the control is telling you

Current only in the run circuit - start circuit is open.

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

  • Failed run capacitor
  • Open start wiring or connection
  • Damaged start winding

Test and repair steps

  1. Warning: Turn off power and discharge capacitor.
  2. Test the run capacitor.
  3. Check start wiring and terminals.
  4. Check the start winding resistance.

Settings for these units

Save it for the next call

Star this code in the HVACopedia app and keep the whole library on your phone for jobs with no signal.

Open the app

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.