Low
d.25 on Vaillant Turbomax Plus VUW 242EH

This code is simply an information display showing whether your boiler's 'instant hot water' pre-heat setting is currently switched on or off.

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

Warmstart status (turboMAX plus) 1 = ON; 0 = OFF

From this model's manual
Verified against the Vaillant Turbomax Plus 824 828e installation & service manual, page 39.
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

Locate the hot water pre-heat button on the front control panelPress the button to toggle the status between 0 (Off) and 1 (On)Observe the display to confirm the setting has changed to your preference

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