BoilerFaultCodesTechnical description
DRY FIRE THERMISTOR ERROR
What causes this fault?
This fault occurs when the boiler fires up but detects an immediate, rapid rise in heat because there isn't enough water circulating to carry that heat away. The most common reasons are a severely trapped pocket of air, a seized pump, or a major blockage in the pipework that is preventing water from reaching the heat exchanger.
This issue is more frequent in autumn when heating systems are switched back on after a long summer break, as pump components can seize up during 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.
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