BoilerFaultCodesTechnical description
Fault codes 9x appear if the condense trap/pipe has become blocked.
What causes this fault?
This fault occurs when the internal safety sensors detect that the waste water produced by the boiler cannot drain away. The most common reason is a physical blockage in the drainage pipe, which causes water to back up into the boiler's internal trap and triggers an automatic shutdown to prevent internal damage.
This fault is extremely common during periods of freezing weather, as the external portion of the condensate pipe can easily freeze and become completely blocked with ice.
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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