BoilerFaultCodes E163 Medium Lockout
Your boiler has detected a problem with the sensor that monitors the temperature of your hot water, meaning you likely have no hot water or it is inconsistent.
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: Domestic hot water (DHW) negative temperature coefficient (NTC) sensor fault (s.c.) or DHW NTC sensor fault (o.c.)
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that measures the temperature of your hot water. The most common reason is that the sensor has physically failed due to electrical wear, or the wiring connecting it to the main control board has become loose or damaged.
Typical repair cost £90-£160 (including labour)
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 E163 — no call-out fees, no surprises.
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