BoilerFaultCodesYour boiler has shut itself down because the internal gases have reached an unsafely high temperature to protect the system from damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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 PP6 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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