BoilerFaultCodesTechnical description
Safety temperature limiter in central heating (CH) flow has tripped the system pressure or safety temperature limiter needs checking
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature, triggering a safety switch to kill the power. The most common reasons are a pump failure that stops water from moving around the system or a build-up of debris causing a blockage in the heat exchanger.
This fault is more common in autumn when the heating is turned back on after a long break, as circulation pumps can often seize up from lack of use.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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