BoilerFaultCodesYour boiler has detected an issue with the sensors that monitor the temperature of your hot water cylinder, which may lead to inconsistent water temperatures.
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: DHW cylinder loading: Starting point -2.5K Stopping point +2.5K
What causes this fault?
This fault occurs when the boiler receives inconsistent or missing data from the probe that monitors your hot water tank. The most common reason is a failing temperature sensor or a loose wire connection, which prevents the boiler from knowing exactly how hot your water is. Without this accurate information, the system cannot safely regulate the heating of your cylinder.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 59:0 — no call-out fees, no surprises.
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