BoilerFaultCodesYour boiler has shut down because the internal water temperature has risen too quickly, suggesting a blockage or a circulation problem.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Heat exchanger temperature too high (Tset + 5K)
What causes this fault?
This fault occurs when the water inside the boiler heats up much faster than the system can carry it away, causing it to reach a dangerous temperature in seconds. The most common reasons are a pump that has stopped working or a buildup of sludge and debris that is physically blocking the flow of water through the narrow channels of the heat exchanger.
This issue often surfaces during the first cold spell of autumn when a pump that has been idle all summer fails to restart or struggles to push through settled debris.
DIY fix possible
Check that all radiator valves and boiler isolation valves are fully openEnsure your central heating system pressure is between 1.0 and 1.5 barPress the reset button to see if the fault clears 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 E13 — 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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