BoilerFaultCodesYour boiler has detected a problem with either its internal water pressure or its temperature safety sensors, which has caused the system to stop working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Water pressure switch or flue thermostat failure
What causes this fault?
This fault occurs when the boiler’s safety controls detect that either the internal water pressure has dropped too low or the exhaust gases have become too hot. It is often triggered by a leak in the system reducing pressure, or a build-up of debris causing the heat exchanger to overheat. In some cases, the sensors themselves may have physically failed or lost their connection to the main control board.
DIY fix possible
Check the pressure gauge on the front of the boilerIf the pressure is below 1.0 bar, use the filling loop to top it up to 1.5 barPress the reset button and wait for the boiler to restart
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 912 — no call-out fees, no surprises.
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Ideal Response SE is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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