BoilerFaultCodesYour boiler's internal thermometer that measures the air around it has stopped working properly, preventing the system from operating safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ambient temperature sensor failure
What causes this fault?
This fault occurs when the boiler's control system loses communication with the sensor that monitors the temperature of the air inside the casing. The most common reason is that the sensor has developed a physical defect or the wiring connecting it to the main control board has become loose or damaged.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like PP5 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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