High
90 on Servowarm Elite HE

Your boiler has detected an incorrect electrical reading from a temperature sensor, causing it to shut down to prevent potential overheating or 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

1277 Ohms

From this model's manual
Verified against the Malvern Combi installation & service manual, page 22.
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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