High
E.00 – .04 on Baxi Suprima 30

Your boiler has stopped working because it cannot accurately measure the temperature of the water returning to the unit due to a faulty or disconnected sensor.

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

Return temperature sensor open-circuit. Sensor not or badly connected.

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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