BoilerFaultCodesTechnical description
Condensate sensor fault
What causes this fault?
This fault occurs when the boiler's internal safety sensor detects that the waste water, known as condensate, is not draining away properly. It is usually caused by a physical blockage in the external pipework or a build-up of debris within the boiler's collector trap. In some cases, the sensor itself may have failed or become corroded, wrongly telling the boiler that it is full of water.
This fault is significantly more common during freezing winter temperatures, as the external condensate pipe can freeze, causing water to back up into the boiler.
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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