High Lockout
EA on Ideal HP290

Your heat pump has stopped working because a sensor that monitors the temperature of the outgoing refrigerant gas is reporting an incorrect or faulty reading.

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

Discharge Thermistor (Tp) Error

What causes this fault?

This fault occurs when the system's control board receives an impossible or unstable temperature reading from the sensor on the compressor outlet. The most common reason is a physical failure of the internal sensor components or a loose wiring connection that prevents the heat pump from safely monitoring its own operating temperature.

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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