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Boiler automatically stops functioning on Malvern 20/26

Malvern 20/26 fault code Boiler automatically stops functioning

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Blocked condensate pipework (e.g., frozen condensate pipework) detected by the syphon trap blocked drain device.

From this model's manual
Verified against the Malvern/Malvern Tentwenty 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 5 fault codes on the 20/26

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

Lockout lamp illuminating (Flue Thermostat)Lockout lamp illuminating (Overheat Thermostat)Phase reversed neon (behind the knob) lightingRunning lamp flashing

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