High
FLOW/RETURN SENSOR DRIFT ERROR on Johnson Starley J32 System ET

Your boiler has detected that the temperature sensors are giving inconsistent readings, which usually happens because the water isn't flowing correctly or the system is low on pressure.

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

Is the heater & CH system filled with water & all isolation valves open?

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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