BoilerFaultCodesTechnical description
Primary return sensor NTC fault
What causes this fault?
This fault occurs when the boiler's main control board suffers a critical electronic failure, preventing it from safely managing the heating process. The most common reasons include a power surge that has damaged the delicate circuitry or components reaching the end of their operational life due to heat stress over several years.
This fault is slightly more common during winter or stormy weather, as power fluctuations and surges caused by grid instability can trip the electronic components on the board.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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