BoilerFaultCodesYour boiler's hot water sensor is struggling to communicate with the main control board, meaning the system cannot accurately monitor the water temperature.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: This indicates an 'open circuit' or 'short circuit' HW sensor or lead.
What causes this fault?
This fault occurs when the boiler's internal computer loses track of the hot water temperature because the sensor has failed or its wiring has become damaged. The most common reason is that the sensor has physically degraded over time or a loose connection has developed, preventing the boiler from safely heating your water.
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 PCB 38 HW light flashing — no call-out fees, no surprises.
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