BoilerFaultCodesYour boiler is struggling to accurately measure the temperature of your hot water, which usually means the water will either be too cold or the system will stop providing hot water altogether.
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 error
What causes this fault?
This fault occurs when the internal sensor responsible for tracking your tap water temperature fails or sends an incorrect signal to the control board. The most common reason is that the sensor has physically degraded over time or developed a faulty electrical connection, preventing the boiler from knowing how much to heat the water. To protect you from scalding or damage, the boiler will usually stop heating the water until the part is replaced.
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 E32 — no call-out fees, no surprises.
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Potterton Powermax HE is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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