High
T6 on Ideal Falcon Gte

Your boiler is struggling to switch to its high-power mode because of an electrical signal failure in its temperature control system.

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

Stage 2 boiler thermostat input / Insert in the control circuit of burner stage 2

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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