Low
d0 on Alpha Intec 40GS2

Your boiler is currently set to a mode where it is adjusting the temperature of the water stored in your hot water cylinder.

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

FlowSmart cylinder temperature adjustment (45 - 78°C)

From this model's manual
Verified against the Alpha Intec 40gs2 installation & service manual, page 28.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check your hot water cylinder thermostat settingsEnsure the temperature is set between 45°C and 78°CRestart the boiler to see if the display returns to normal

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