Condensate drain adaptor is leaking at soil pipe

[mfripp]

We recently had a new combi boiler fitted in our kitchen. The installer used a rubber adapter to fit the condensate pipe directly into a 40mm boss on an adjacent soil pipe (the adaptor is a rubber ring with ridges around the outside and inside).

Now, before putting drywall over this area, I've checked the connection at the soil pipe, and it seems to be slowly leaking. I think this is probably waste water from the flat above ours, coming in around the outside of the adaptor.

Is there a more secure way to connect the condensate drain to this boss? The boss itself is gray plastic and looks like it may have a rubber ring around the inside to allow "push-fitting" a standard 40mm pipe. I want to be sure there won't be a slow wastewater leak behind the new cabinets!

(The sink drain used to be connected to this boss, but we moved it to a different boss while re-doing our kitchen, since this one is at a slightly funny angle.)

Photo attached, in case that's helpful.

 

[mfripp]

On closer inspection, it looks like he has inserted a 32-40mm solvent weld adapter into the soil pipe boss, then used a rubber 32-19mm adapter, and inserted the 22mm overflow pipe into that. I suppose this should work in theory, but it doesn't seem to be watertight.

Should I remove the rubber adapter, solvent weld a 32mm pipe into the 32-40mm adapter, and then attach an upward-pointing elbow, and connect the rubber adapter into that from above? Or remove the 32-40mm adapter entirely (not easy or pleasant) and use a 40mm pipe + elbow, then push all the adapters into that elbow from above?

 

[wards]

get the installer back to sort it out,i am sure if he is reputable he will oblige.

 

[mfripp]

Well, unfortunately we went with the cheapest installer, and he hasn't proved so "reputable". So I'm looking for a quick and effective way to fix this myself and move on with the rest of the project.

 

[ocentric]

It may be that the condensate pipe is too long & protruding too far into the soil pipe and allowing the waste water to track back along. That said, the rubber should stop this. Did he use a new rubber seal?

 

[mfripp]

The rubber adaptor seems to be new, and as far as I can tell the water is coming out around the outside of this adaptor. I pulled the rubber adaptor out at one point, and there seemed to be a little bit of water pooling inside the 32-40mm pvc adapter that it slips into. This is not surprising since we sometimes get blasts of air out of this soil pipe when water rushes down (a separate problem!). I think that that water is able to get around the outside of the 32-22mm rubber adapter when it inserted into the 40-32mm pvc adapter.

Maybe this wouldn't be a problem if all the adapters faced down into an elbow or tee, instead of horizontally into the soil pipe boss?

 

[dontknowitall]

Pays peanuts, gets monkeys!

But then again, who out of all of us hasn't tried to cut a major corner or two with a major financial outlay at some stage in our lives?

mfripp - If you take this pic down to your plumbing merchant they should be able to sort you out. Alternatively, you could phone a local independent plumber (different one!)

 

[GPSNewcastle]

If you want to be sure that this isnt going to leak behind the wall then rip out the push fit boss and replace with solvent weld (solvent weld adaptor glued to solvent pipe isnt going to leak).

 

[mfripp]

Thanks for all the advice!

I finally took the whole thing apart and found that the 32-40mm adaptor wasn't compatible with the 40mm soil pipe boss. The soil pipe boss has a rubber flange around the inside of its entrance, which is designed to seal against a 40mm pipe. However, the 32-40mm adaptor was only about an inch "long", and was pushed in past this gasket, so there was no real seal around the adaptor. (As far as I know, the 22-32mm adaptor was actually sealing fine; it just looked like the water was coming from that because the rubber gasket completely obscured the 32-40mm adaptor.)

It was a giant pain to remove the 32-40mm adaptor, because the rubber flange acts as a sort of one-way barb. I eventually had to cut through the adaptor with a hacksaw blade and Stanley knife. Once I got it out, I put in a length of 40mm UPVC pipe, and attached the condensate line to it using solvent-weld 22-32mm and 32-40mm adaptors. It all seems to be working much better now!

Along the way I also discovered that the installer had used polypropylene push-fit pipes with UPVC elbows and solvent adhesive. The polypropylene pipes were completely unaffected by the solvent adhesive, and could be removed easily with a firm twist. It probably would have been safe for a while (since the PP pipes are meant to be push fit with UPVC connectors anyway), but I switched everything over to solvent weld just to be sure.