BoilerFaultCodesTechnical description
Appears if a problem exists with the condense sensor.
What causes this fault?
This fault occurs when the boiler's safety sensor detects that the acidic water, known as condensate, is not draining away correctly. The most common reason is a blockage in the internal condensate trap or a buildup of debris around the sensor itself, which triggers the system to stop as a safety precaution. In some cases, the sensor may have failed electronically or the wiring connecting it to the main control board has been damaged.
This fault is more common during extreme cold snaps, as the external portion of the 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.