High
213 on Worcester Bosch 1000

Your boiler has detected that the water leaving the boiler is much hotter than the water returning to it, suggesting the system is struggling to circulate heat properly.

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

Temp difference between supply and return exceeding limit

What causes this fault?

Temperature differential fault

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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