Ideal Standard ICOS. No codensate waste ??

The stuff that drips out the flue is the stuff that *doesn't* condense inside the boiler. The condensate pipe is normally around 22mm plastic pipe from below the boiler and probably connects to a trap inside the house.

Mr F.

On a condensing boiler the flue is usually installed at a slight upward angle to ensure any condensate runs back into the boiler...

If there was no condensate drain, then the build-up of corrosive condensate would start to fill the combustion chamber and wreck it, eventually corroding through and leaking out. I would have expected your son to already be experiencing problems with his boiler after 1 year if it has no condensate drain-off. Have a good poke around underneath, there'll be a drain-off there somewhere - betcha.

Angus

Generally, won't run for longer than a few hours without a condensate drain. The condensate level in the combustion chamber raises and blocks off the flue (or other vital opening, depending on boiler design), at which point the boiler goes out. However, it shouldn't corrode any faster, as the combustion chamber is in any case being washed down by condensate in normal operation.

Agreed, although the collar between the combustion chamber and the condensate trap used to be perishable on the first ISARs, hence making it extremely important to flush the trap out during the annual service. I've seen one blocked, where the standing condensate had brought a resonably new ISAR close to ruin.

Angus

For ISAR, read ICOS!!!

Angus

TNX, a lot.

It's just the boiler is mounted, isolated in a high level wall cupboard, I saw the flue going out, the flow & return, plus the cold feed and gas pipe but nowt else, certainly no 22mm pipeage..

I'll look again next time I go.

DG