High
46 on Johnson Starley Reno HE

Your boiler has lost communication with a sensor that monitors the temperature of the exhaust gases, causing it to shut down for safety reasons.

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.

What the manual says

Manufacturer manual

Flue gas temperature sensor open circuit, Temperature sensor not connected or failed

From this model's manual
Verified against the Johnson Starley Bm Johnson Starley Amp Johnson Reno Starley He16h He25h He31h He16hp He25hp He31hp installation & service manual, page 24.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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