BoilerFaultCodesYour boiler has reached its maximum power limit while trying to heat your water, and it has stopped for a short time to prevent overheating.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Max. combustion point reached
What causes this fault?
This fault occurs when the boiler generates more heat than the system can successfully carry away, leading to a sudden temperature spike. The most common cause is a restriction in water flow, often due to a failing internal pump or a buildup of sludge and debris blocking the main heat exchanger. It essentially means the boiler is working too hard to push heat into a system that isn't circulating properly.
This issue often becomes more apparent during winter when the boiler is required to run at higher power levels for longer periods to meet central heating demands.
DIY fix possible
Check that all your radiator valves are fully openEnsure your system pressure is topped up to between 1.0 and 1.5 barPress the 'Reset' button on the front of the screen to clear the temporary lockout
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 1013 — no call-out fees, no surprises.
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