BoilerFaultCodesYour boiler has detected that the water returning from your radiators is too hot, causing the system to shut down to prevent overheating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return sensor temperature exceeded
What causes this fault?
This fault occurs when the boiler detects that the water coming back from your heating system is at an unsafely high temperature. The most common reasons are a blockage in the pipes, a faulty pump that isn't moving water fast enough, or a sensor that has developed a technical fault and is giving a false reading.
This issue often appears at the start of winter when the heating is turned on for the first time after summer, as internal pump parts can seize during long periods of inactivity.
DIY fix possible
Check that at least two or three radiators have their valves fully openEnsure your magnetic system filter is clean and not blockedCheck if the pump is running or if there is a blockage in the pipework
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 E19 — no call-out fees, no surprises.
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Vokera Hydra 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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