BoilerFaultCodesYour boiler has shut down because it has detected that the water inside has become dangerously hot, causing the safety overheat thermostat to trip.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow temperature too high (STB)
What causes this fault?
This fault occurs when the water leaving the boiler exceeds a safe temperature limit, causing the system to shut down to prevent damage. The most common reason is a lack of water circulation, often caused by a failed pump or a blockage in the heat exchanger that prevents heat from being carried away quickly enough.
This issue is more frequent during the first cold spell of autumn when a pump that has been idle all summer may seize or struggle to move heavy sludge that has settled.
DIY fix possible
Check that all radiator valves are fully openEnsure the central heating system pressure is between 1.0 and 1.5 barPress the 'Reset' button on the boiler control panel once the unit has cooled 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 E07 — no call-out fees, no surprises.
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Remeha Quinta 115 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.
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