BoilerFaultCodesTechnical description
Low temperature zone room thermostat intervention
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the system is getting too hot or that water isn't moving through the unit correctly. It is often triggered by a circulation issue, such as a failing pump or a blockage, which causes the heat exchanger to reach a dangerous temperature. To prevent any damage, the boiler automatically shuts down and locks itself for your safety.
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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