T2B High

Ideal T2B Fault Code

The Ideal T2B fault code means: your heat pump has stopped working because a sensor that monitors the temperature of the internal cooling liquid has detected a problem or failed.. It appears on 1 Ideal model in our database.

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: Refrigerant Thermistor Error

What causes the Ideal T2B fault?

This fault occurs when the system's control board loses communication with the sensor that monitors the temperature of the refrigerant liquid. The most common reason is that the sensor itself has developed an electrical fault or the wiring connecting it to the main controller has become loose or damaged. Because the unit cannot safely monitor these internal temperatures, it shuts down to prevent damage to the compressor.

Typical repair cost £180-£350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Ideal models that show the T2B fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ideal T2B fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026