Medium Lockout
E06 on Ideal Mini S15

Your boiler is having trouble measuring the temperature of your hot water, which usually means it cannot provide consistent heat to your taps.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

DHW thermistor error

What causes this fault?

This fault occurs when the sensor responsible for monitoring the temperature of your hot water fails or sends an incorrect signal to the boiler's control board. The most common reason is that the internal components of the sensor have degraded over time or developed a lime scale coating, preventing it from reading the heat accurately. In some cases, the error is caused by loose or corroded electrical connections between the sensor and the main unit.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E02View →E05View →

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