Vaillant EcoTec Boiler won't stay fired on

[taylorwright]

Hi all,

Been having a rather annoying problem with our boiler (Vaillant ecotec 637 plus).

A few days ago, it developed a problem whereby it cannot ignite any more (or on it's own at least, more below). What happens is that it tries to ignite, but the flame very quickly dies away. It tries to do this several more times before giving up and displaying an F.28 code. I have already checked the condensate pipe and it is not blocked. We have another identical boiler connected to the same gas supply and is functioning properly. So i assume there is no gas supply issue.

When i said it can start with some assistance, i have found that if i slightly block the air intake using a cloth (as it tries to ignite), then the flame will hold and it can work for hours normally. At some point, the boiler will turn off after reading the desired temperature, but then wont ignite itself again.

Could it be that the air intake fan is blowing too much air into the chamber, and putting out the flame?

I have called a Gas Safe engineer already, but couldn't find something at fault.

Any idea anyone?

 

[ScottishGasMan]

Sorry but DIY gas info is not allowed on here, and blocking air intakes with cloths can be a rather risky business.

If your gas safe engineer cant find a fault on a boiler that clearly isnt working then I suggest looking for someone more reputable or experienced. (I can understand intermittent faults can be a pain for the most experienced guys, but a boiler that wont work in front of you should be relitavly straight forward.