High
ALL 22 on Sime Murelle HE 35 R

Your boiler has detected that a safety thermostat on your underfloor heating or mixed temperature zone has tripped, causing the system to shut off that zone for protection.

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 a mixed zone board is connected to the boiler, an intervention of the safety thermostat switches on the mixed zone pump, the mixed zone valve closes and the display indicates ALL 22.

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 21View →ALL 23View →

All 36 fault codes on the Murelle HE 35 R

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

ALARM 70ALARM 71ALL 02ALL 05ALL 06ALL 07ALL 08ALL 09ALL 13ALL 14ALL 15ALL 21ALL 23ALL 24ALL 25ALL 26ALL 27ALL 28ALL 29ALL 30ALL 31ALL 32ALL 33ALL 34ALL 35E0E1E2E3E4E5E6E7E8E9

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