BoilerFaultCodesYour boiler's temperature sensor for hot water is failing, meaning the system cannot accurately heat water for your taps.
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: Flashing lamp, alternate with another lamp.
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring hot water temperature becomes corroded or develops an electrical resistance failure. Over time, constant heating and cooling cycles can cause the sensor to degrade, preventing it from sending an accurate signal to the boiler’s main 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.
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