Rheem · Heat pump

27 Low line voltage or no line voltage

Medium severity Rheem/Ruud PRL-JEC heat pump (Comfort Control2 ICC)

What the control is telling you

The ICC detects low or missing line voltage.

Applies to: (-)PRL-JEC 2-stage 16 SEER heat pumps: RPRL/UPRL-024JEC, -036JEC, -048JEC, -060JEC

Likely causes

Low utility voltage
Tripped breaker/fuse or open disconnect
Loose or undersized power wiring

Test and repair steps

Measure line voltage at the disconnect and at the unit; operating range for 208/230V units is 197-253V.
Check fuses/breaker and disconnect.
Check and tighten wiring connections at the ICC L1/L2 lugs (torque per wire size, check annually).
If the utility supply is low, have it corrected before further diagnosis.

Settings for these units

Outdoor unit clearances · Rheem/Ruud PRL-JEC heat pump (Comfort Control2 ICC)

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Source: Rheem (-)PRL-JEC Heat Pump Installation Instructions, 12.6 ICC Diagnostic Codes, p.30. 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.