BoilerFaultCodesYour boiler has detected a problem with the sensor that monitors hot water temperature, meaning you likely have no hot water or the temperature is inconsistent.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Domestic hot water (DHW) negative temperature coefficient (NTC) thermostat sensor fault (s.c.) or DHW NTC sensor fault (o.c.).
What causes this fault?
This fault occurs when the sensor responsible for measuring the temperature of your hot water fails or sends an unreadable signal to the main control board. The most common reason is that the internal components of the sensor have worn out over time, or the electrical connection between the sensor and the boiler has become damaged or loose.
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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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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