High Lockout
T2 on Ideal HP290

Your heat pump has detected a problem with a temperature sensor inside the outdoor unit, which has caused the system to stop working to protect itself.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Outdoor Unit, Plate Heat Exchanger Outlet Refrigerant Thermistor (T2) Error

What causes this fault?

This fault occurs when the control system receives an incorrect or missing signal from the sensor that monitors the temperature of the refrigerant as it leaves the heat exchanger. The most common reason is a physical failure of the sensor's internal components or loose electrical connections caused by the constant vibrations of the outdoor unit.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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