BoilerFaultCodesYour boiler is limiting the temperature it uses to heat your hot water tank to prevent it from getting too hot.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Limitation of cylinder charging temperature in c
What causes this fault?
This issue occurs when the boiler detects that the temperature being sent to your hot water tank is too high for the cylinder's safe operating limits. It is usually caused by a faulty temperature sensor providing incorrect readings or a communication error in the wiring between the boiler and the tank. As a safety precaution, the boiler automatically scales back its heat output to prevent the water from overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like D.78 — no call-out fees, no surprises.
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