How much does it cost to fix Ideal error code 85 H.....2.....?

Typical repair cost for the Ideal 85 H.....2..... fault is £120-220 including labour.

85 H.....2..... High

Ideal 85 H.....2..... Fault Code

Q: What does the Ideal 85 H.....2..... fault code mean?

Your boiler has lost the ability to accurately measure the temperature of the water returning to it, so it has safely shut down to prevent overheating.

Also written as 85H2 — same fault.

The Ideal 85 H.....2..... fault code means: your boiler has lost the ability to accurately measure the temperature of the water returning to it, so it has safely shut down to prevent overheating.. It appears on 2 Ideal models in our database.

Technical description: CONTROL THERMISTOR [RETURN] ERROR

Typical repair cost £120-220 (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 85 H.....2..... fault code

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

Source

Ideal 85 H.....2..... 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