Low
d2 on Alpha Intec S

This code is simply an information display showing the current temperature of the water leaving your boiler to heat your home, rather than a sign of a fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Central heating water temperature leaving the boiler °C

From this model's manual
Verified against the Alpha Intec S installation & service manual, page 27.
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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