Medium
I.020 on Vaillant ecoTEC plus

Your boiler's water pressure has dropped too low, which is stopping it from circulating heat effectively around your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

The water pressure in the heating system is at the lower limit.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 92.
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 filling loop (a silver flexi-hose) underneath your boiler or near your pipework.Open the small valve(s) on the loop to allow mains water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valve(s) firmly once the correct pressure is reached to stop the flow.

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