Unknown
AL28 on Pro A36

Pro A36 fault code AL28

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Temperature differential inverted (return sensor temperature higher than thermistors flowsensor temperature)

From this model's manual
Verified against the Pro/Pro A28 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 16 fault codes on the A36

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

10AL10AL20AL21AL26AL34AL40AL41AL52AL55AL60AL71AL73AL74AL79

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