BoilerFaultCodes Fault 51 132 Medium Lockout
Your boiler has lost communication with the temperature sensor that monitors your hot water cylinder, meaning it cannot accurately heat your water.
Book a service
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: Temperature sensor type PTC 1000 used as cylinder temperature sensor (T2).
What causes this fault?
This fault occurs when the boiler's control board can no longer detect a signal from the sensor attached to your hot water tank. It is usually caused by the sensor itself failing internally or the electrical wiring becoming loose or damaged over time, preventing the boiler from knowing how hot your water is.
Typical repair cost £90-180 (including labour)
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 Fault 51 132 — no call-out fees, no surprises.
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