High
285 on Worcester Bosch Greenstar CDi Compact

Your boiler has detected that the water returning to it is dangerously hot and has temporarily switched itself off to prevent system damage.

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

Return temperature exceeds 95°C The boiler will stop the burn and wait to see if it cools down. If after 2 seconds there is an increase in temperature the boiler will go to Locking error 286.

From this model's manual
Verified against the Worcester Bosch Greenstar Cdi Compact installation & service manual, page 65.
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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