FLOW/RETURN SENSOR DRIFT ERROR High

Johnson Starley FLOW/RETURN SENSOR DRIFT ERROR Fault Code

Q: What does the Johnson Starley FLOW/RETURN SENSOR DRIFT ERROR fault code mean?

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.

Q: How much does it cost to fix Johnson Starley error code FLOW/RETURN SENSOR DRIFT ERROR?

Typical repair cost for the Johnson Starley FLOW/RETURN SENSOR DRIFT ERROR fault is £90-180 including labour.

Also written as FLOWRETURNSENSORDRIFTERROR — same fault.

The Johnson Starley FLOW/RETURN SENSOR DRIFT ERROR fault code means: 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.. It appears on 1 Johnson Starley model in our database.

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

Typical repair cost £90-180 (including labour)

DIY fix possible

Check the system pressure gauge and top up with water if it is below 1.5 barEnsure all radiator valves and boiler isolation valves are fully openBleed all radiators to remove trapped air that might be blocking water flow

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Johnson Starley models that show the FLOW/RETURN SENSOR DRIFT ERROR fault code

Click a model for the full fault code list and model-specific repair notes.

J32 System ET Repair: £90-180

Source

Johnson Starley FLOW/RETURN SENSOR DRIFT ERROR fault code information on this page is sourced and cross-checked against the official Johnson Starley service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026