BoilerFaultCodesYour heat pump has stopped providing hot water because a sensor that monitors the water temperature has developed a fault or is disconnected.
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 (T5) Error
What causes this fault?
This fault occurs when the heat pump loses communication with the sensor monitoring the temperature inside your hot water cylinder. The most common reason is that the sensor has failed internally due to wear, 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.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 9.1.6 — 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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