Vaillant ecoTEC PLUS 418 service

vaillant-ecotec-plus-418

This was a standard annual service of a Vaillant ecoTEC PLUS heat-only boiler in Ecclesfield, Sheffield S5, done in August 2018.

I started looking after this boiler back in 2015 a year after it had been installed.

This customer has had me back each year for its annual service. So far it has been a reliable boiler with no issues.

The Vaillant ecoTEC heat-only boilers require very little maintenance and are quite reliable in general, but can suffer from a few issues which is why they should be checked periodically.

The older Glowworm hxi heat-only, and the Vaillant ecoMAX PRO heat-only boilers share a similar design to the Vaillant ecoTEC PLUS heat-only boilers and share the same problems. The top half of these boilers are essentially the same as the ecoTEC PLUS, although the bottom half is different and they use different printed circuit board’s.

One of the issues is the failure of the flue gas conveyor, which is a plastic manifold behind the heat exchanger which carries the flue gasses. These can split which causes the flue gasses to leak out and condensation starts to corrode the inside of the boiler casing. This is a safety issue and can destroy a boiler casing fairly quickly if it is not picked up. This is something that should always be checked on a service.vaillant-flue-gas-conveyor

The condensate traps are less of an issue but these can leak as well from the pipes or the top of the trap. This can also constitute a safety issue and cause corrosion on the casing.

vaillant-ecotec-plus-418-condensate-trap

Early versions of these boilers had problems with the burner door seal failing, which is essentially the gasket that seals between the burner and heat exchanger. These issues were subsequently fixed with a graphite gasket being the solution, although there are still boilers I come across from time to time with the original problematic burner door seals. Usually these are failing and I replaced them.

vaillnt-burner-door-seal

Although the graphite seals don’t tend to fail, on Vaillant boilers with this ecoMAX style heat exchanger, there is a rubber seal on the bottom which always deteriorates and needs to be replaced periodically otherwise it starts to leak. Although directly this does not typically result in a boiler failing.