Mitsubishi Ecodan P2 fault code
Mitsubishi Ecodan heat pumps
What it means
Liquid refrigerant thermistor (TH2) open/short
Open ≤ −39 °C, short ≥ 88.5 °C. Not raised during defrost or for 10 minutes after — retest outside that window before condemning.
Safety: Safe isolation before disconnecting sensors or working on the PCB.
UK models this code applies to
From the Mitsubishi Electric service literature we hold (Ecodan FTC service manual, error-code chapter + §10-6 thermistor tables) — not a scraped list.
Ecodan PUZ-WM50VHA (R32)Ecodan PUZ-WM60VAA (R32)Ecodan PUZ-WM85VAA (R32)Ecodan PUZ-WM85YAA 3-phase (R32)Ecodan PUZ-WM112VAA (R32)Ecodan PUZ-WM112YAA 3-phase (R32)Ecodan PUZ-WZ50VAA (R290)Ecodan PUZ-WZ60VAA (R290)Ecodan PUZ-WZ85VAA (R290)Ecodan PUZ-WZ85YAA 3-phase (R290)Ecodan PUZ-WZ100VAA (R290)Ecodan PUZ-WZ100YAA 3-phase (R290)Ecodan PUZ-WZ120VAA (R290)Ecodan PUZ-WZ120YAA 3-phase (R290)
Now the harder half: proving what caused it
P2 names a symptom, not a root cause. In the app, the same code opens a guided investigation: what to measure first, the expected values for your exact model, and an honest verdict — including “nothing in this machine is broken” when that's what the readings say.
Chase this code in the app →