BoilerFaultCodesYour boiler has lost its connection to the sensor that monitors the temperature of the water in your heating system, causing the boiler to stop working.
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 boiler's control board can no longer read the temperature of the water leaving the unit. The most common cause is a failed internal sensor that has either burnt out or developed an electrical fault, though it can also be triggered by a loose or damaged connection in the internal wiring.
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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