High
EE 0077 on Ariston Microsystem 15

Your boiler's temperature sensor is sending an incorrect electrical signal, which is preventing it from safely heating your water or home.

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

Heating flow temperature probe in short-circuit

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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