Mitsubishi Heat Pump Error Codes
Mitsubishi Electric heat pumps are the most popular ductless systems in BC and a mainstay of FortisBC and BC Hydro rebate installs. They self-diagnose and flash an alphanumeric code (P-, E- and U-series) on the indoor unit or remote. The conditions below cover the faults we see most across the Lower Mainland.
How Mitsubishi shows faults: Mitsubishi heat pumps show an alphanumeric code on the indoor unit LED or the remote display (P-series = indoor protections/sensors, E-series = communication, U-series = outdoor/compressor). The conditions below explain the common ones.
Indoor/Outdoor Communication Error
highYour Mitsubishi Electric mini-split or multi-zone system lost the data link between the indoor and outdoor units, so it stops. Often shown on the indoor LED or remote as an E6/E7-type communication code.
Indoor Coil / Intake Thermistor Fault
moderateAn indoor temperature thermistor (room intake or pipe sensor) is reading out of range, so the system cannot control capacity correctly. Often a P1/P2-type code on Mitsubishi units.
Freeze-Up or Overheat Protection
moderateThe unit tripped a protection because the indoor coil iced up in cooling or ran too hot — a P6-type protection on Mitsubishi systems.
Outdoor Unit / Compressor Protection
highThe outdoor unit reported a compressor, inverter or power fault and shut the system down (U-series codes such as U4 on Mitsubishi).
Low Refrigerant / Loss of Charge
highThe system is detecting abnormal pressures or temperatures consistent with low refrigerant — it will lose heating/cooling capacity and may trip protections. Refrigerant work is licensed in BC.
Condensate Drain / Float Switch Fault
moderateA wall-mounted or ducted indoor unit tripped its drain protection because condensate is not clearing — a P5-type drain fault on Mitsubishi units.
Need a Mitsubishi technician in Greater Vancouver?
Furnace and heat-pump service is handled by our parent company, CANRO Heating & Cooling — same-day & after-hours. Call 604-359-1081.
Mitsubishi heat pump acting up?
CANRO Heating & Cooling — same-day diagnosis across Greater Vancouver. Call 604-359-1081.