BoilerFaultCodesTechnical description
Discharge gas overheat protection
What causes this fault?
This fault occurs when the internal temperature of the combustion gases becomes too high, triggering a safety shutdown to prevent the boiler from melting or cracking. The most common causes are a failure in the pump preventing water from moving heat away quickly enough, or a build-up of sludge and debris that has blocked the heat exchanger.
This issue often surfaces during the first cold snap of winter when the boiler is suddenly required to run at maximum output for long periods.
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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