BoilerFaultCodesYour boiler is struggling to correctly measure the temperature of your hot water, which may lead to lukewarm water or no hot water at all.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Fault on Hot Water Sensor
What causes this fault?
This fault occurs when the boiler's internal computer can no longer read a reliable signal from the sensor responsible for monitoring your tap water temperature. The most common reason is that the sensor has either suffered water damage from a small leak or has simply worn out over years of constant heating and cooling.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 27 — no call-out fees, no surprises.
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