BoilerFaultCodesWhat the manual says
Manufacturer manualSAFETY TEMPERATURE LIMITER
What causes this fault?
This fault occurs when internal sensors detect that the water inside the boiler has exceeded a safe temperature limit, triggering an emergency shutdown to prevent damage. The most common reason is that the pump has stopped moving water around your radiators, or a buildup of debris has created a blockage that traps heat inside the unit.
This issue is frequently seen when the heating is first switched on after summer, as circulating pumps can often seize up during long periods of inactivity.
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.
Avoid the next call-out bill
A cover plan would handle faults like NEON5: no call-out fees, no surprise bills.
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