BoilerFaultCodesWhat the manual says
Manufacturer manualSAFETY TEMPERATURE LIMITER
From this model's manual
Verified against the Glow Worm Hideaway 40b installation & service manual.
What causes this fault?
This fault occurs when the internal temperature of the boiler exceeds safe limits, triggering a safety shut-off to protect the system. The most common reason is a lack of water flow, often caused by a failing circulation pump or a blockage in the heat exchanger preventing heat from being carried away. In some cases, it can also be triggered by a faulty sensor giving an incorrect high-temperature reading.
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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