BoilerFaultCodesTechnical description
Temperature too high during DHW demand.
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the domestic hot water has reached an unsafely high temperature. The most common reasons are a buildup of limescale inside the heat exchanger restricting water flow, or a faulty sensor that is sending incorrect temperature readings to the main control board.
This issue often becomes more apparent in summer when the incoming mains water is naturally warmer, making it easier for the boiler to exceed its maximum temperature limit.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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