BoilerFaultCodesYour boiler has shut down because the water inside has become too hot, usually due to a lack of circulation or a blockage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Max.water temperature: Flow temperature too high.
What causes this fault?
This fault occurs when the water leaving the boiler exceeds its safe temperature limit, causing the system to shut down for safety. The most common cause is a failed internal pump that isn't moving water away from the burner quickly enough, or a significant blockage within the heat exchanger that is restricting flow. It can also be triggered by a faulty sensor that is incorrectly reporting the water temperature as being too high.
This issue is more frequent in autumn when heating systems are switched back on after a long summer break, as internal pump components are prone to seizing during periods of inactivity.
DIY fix possible
Check that all radiator valves are fully open to allow water flowEnsure the boiler pressure gauge is between 1.0 and 1.5 barPress the reset button once the boiler has had time to cool down
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 1 8. — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Remeha W40 60 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
Affiliate links — we may earn a commission at no extra cost to you.