Vaillant's ecoTEC Plus range is a common sight in newer UK installations, known for running quietly and efficiently — but like any boiler, it develops faults over time, and Vaillant-specific codes don't always mean the same thing as the equivalent code on a different brand.
Common Vaillant faults
- Failed ignition or loss of flame (F.28)
- Poor circulation, low pressure, or a pump fault (F.75)
- Water pressure too low (F.22)
For more codes across other brands, see our error codes page.
Genuine customer feedback
"Arrived promptly to repair my Vaillant boiler after another company let me down and left me without heating and hot water for days. Had it running again within the hour."
Verified customer · MyBuilder
Beyond economical repair? New boilers are fitted from £1,999 by our installation arm — see Birmingham Boiler Installation.
Models we see most
Most Vaillant callouts involve the ecoTEC Pro and ecoTEC Plus combis — fitted in large numbers across newer Birmingham installations — along with the more recent ecoFIT Pure range and older ecoTEC models still going strong past their warranty. All diagnosable the same way: £99 including the first hour.
Frequently asked questions
Do you carry Vaillant parts?
Common failure parts are stocked on the van generically. Vaillant-specific parts are sourced same or next day where suppliers have them — quoted before fitting, with a 12-month parts warranty on most repairs.
What does Vaillant F.28 or F.29 mean?
Both relate to ignition or flame failure — the boiler couldn't light or lost its flame. In freezing weather a frozen condensate pipe is a common trigger, so check that first. One reset per the manual is fine; if the code returns, book a diagnosis rather than keep resetting.
My ecoTEC keeps losing pressure — is that a known thing?
Pressure loss isn't unique to Vaillant — the causes are the same on any sealed system: a small leak, a weeping pressure relief valve, or a failing expansion vessel. Our losing pressure guide covers what's safe to check before we come out.