BoilerFaultCodesYour boiler is having trouble measuring the temperature of your hot water, likely meaning you won't have any hot water available.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: DHW THERMISTOR FAULT
What causes this fault?
This fault occurs when the sensor responsible for monitoring your hot water temperature has failed or is sending incorrect electrical signals back to the main control board. Over time, these sensors can degrade due to constant heat cycles or internal corrosion, leading the boiler to shut down for safety because it can no longer regulate water temperature correctly.
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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