BoilerFaultCodes 414 Medium Warning
Your boiler has lost communication with the temperature sensor responsible for the third heating zone in your home, meaning that specific area may not heat correctly.
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: Room sensor circuit open or short circuit zone 3
What causes this fault?
This fault occurs when the boiler loses its electrical connection to the thermostat or sensor that controls your third heating zone. The most common reason is a loose or damaged wire between the boiler and the sensor, or a technical failure within the sensor unit itself.
Typical repair cost £90-180 (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 414 — no call-out fees, no surprises.
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