BoilerFaultCodesYour boiler has detected that the water leaving the unit is getting too hot, causing it to shut down to prevent damage.
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
What causes this fault?
This fault occurs when the water inside the boiler heats up too quickly or exceeds a safe temperature limit. The most common reasons are a pump failure that stops water from moving through the system, or a buildup of limescale and sludge that restricts flow within the heat exchanger.
This issue often surfaces during the first cold spell of autumn when the heating is turned back on after being idle all summer, which can cause internal pump parts to seize.
DIY fix possible
Check that all radiator valves are fully openCheck that the external pump (if visible) is running and not stuckWait 20 minutes for the unit to cool down and try resetting the boiler
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 H1 — no call-out fees, no surprises.
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Ideal Classic M3050 M5080 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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