High
ALARM 70 on Sime Murelle HE 35 R

Your boiler has detected an issue with the sensor that monitors shared heating systems or multi-boiler setups, causing it to temporarily stop working safely.

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

When an anomaly affects cascade operation (cascade delivery sensor ALL 31)

From this model's manual
Verified against the Sime/Sime Murelle He Regular installation & service manual.
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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Related fault codes

ALL 31View →ALARM 01View →ALARM 02View →

All 36 fault codes on the Murelle HE 35 R

Seeing a different code? Every code this model can display, in one place.

ALARM 71ALL 02ALL 05ALL 06ALL 07ALL 08ALL 09ALL 13ALL 14ALL 15ALL 21ALL 22ALL 23ALL 24ALL 25ALL 26ALL 27ALL 28ALL 29ALL 30ALL 31ALL 32ALL 33ALL 34ALL 35E0E1E2E3E4E5E6E7E8E9

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