BoilerFaultCodesYour boiler's temperature sensor for the heating system has stopped communicating correctly, meaning your boiler doesn't know how hot the water is and will likely stop running for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Central Heating NTC Fault
What causes this fault?
This fault occurs when the internal sensor responsible for measuring the temperature of the water in your radiators becomes damaged or develops an electrical glitch. The most common reason is that the sensor has physically degraded or developed a short circuit, preventing it from sending a reliable reading to the boiler’s control board.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E20 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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