High Lockout
E32 on Potterton Powermax HE

Your 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.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 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 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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Related fault codes

E31View →E11View →

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