Boiler condenser pipe letting water back

fossman

We had a boiler fitted in February 2022 and have noticed recently the condenser pipe is letting a small amount of water back into the house.

The condenser pipe comes out of the bottom of the boiler and then directs left and connects to a larger pipe in the wall with an overflow reducer.

The water is coming back through the reducer and pooling on the edge of the larger pipe (see picture).



I tried contacting the installer but it is outside the 12 month warranty on installation.

Is this something I can sort myself with some sealant or do I need to contact a professional.

jefaz07

You could dry it and try to fill the gaps with solvent cement. Let it go off and hopefully will solve it. 

xzibit

A bit of plumbers mate will sort that. It’s not pressurised. Ours started dripping on the connection on the outlet from the boiler. Plumbers mate sorted it. 

ThisIsWeird

fossman said:

We had a boiler fitted in February 2022 and have noticed recently the condenser pipe is letting a small amount of water back into the house.

The condenser pipe comes out of the bottom of the boiler and then directs left and connects to a larger pipe in the wall with an overflow reducer.

The water is coming back through the reducer and pooling on the edge of the larger pipe (see picture).



I tried contacting the installer but it is outside the 12 month warranty on installation.

Is this something I can sort myself with some sealant or do I need to contact a professional.

That's the indoor pic? Could we see the outside too, please?

Best, if possible, to seal this on the outside.

And do you know if this is rain, or could it be the condensate from the pipe? Does it only happen when it rains?!

housebuyer143

My dad had his overflow attached to the downpipe and the boiler flooded when they had a storm as the water backed up the downpipe and then backed up through the overflow as it couldn't drain fast enough and came out the boiler. 
Are you saying that overflow is attached to the drainpipe?

fossman

ThisIsWeird said:

fossman said:

We had a boiler fitted in February 2022 and have noticed recently the condenser pipe is letting a small amount of water back into the house.

The condenser pipe comes out of the bottom of the boiler and then directs left and connects to a larger pipe in the wall with an overflow reducer.

The water is coming back through the reducer and pooling on the edge of the larger pipe (see picture).



I tried contacting the installer but it is outside the 12 month warranty on installation.

Is this something I can sort myself with some sealant or do I need to contact a professional.

That's the indoor pic? Could we see the outside too, please?

Best, if possible, to seal this on the outside.

And do you know if this is rain, or could it be the condensate from the pipe? Does it only happen when it rains?!

It is definitely not rain water as I was in the kitchen today when the boiler was on and I heard the water coming out through the condenser pipe. I looked at the pipework at the wall and witnessed the water coming back through.

The water is coming back through the centre hole in the reducer that the white pipe goes through (the water is coming in around the underside of the white pipe).

ThisIsWeird

Ah, I see - it's one of these: https://www.screwfix.com/p/floplast-overflow-waste-reducer-white-21-5-40mm/44361
Could you post a wider shot showing the white pipe on its way to that point, please? Is there any 'play' in it that would allow the pipe to be pulled out to check why this is happening? 
How many connectors on it - any just push-tight and not solvented so could be dismantled?
Would still like to see the outside situation too; can you see the final end of the larger pipe where the condensate comes out, to check it isn't backed up as hb143 says?
Strange - that 'should' be a snug, sealed fit.

fossman

This is the full pipe on it's way to the wall.

There is not enough play to pull the pipe out of the reducer. How can I tell if they are push-tight rather than solvented?

Where the pipe meets the reducer there does appear to be some "dried glue" marks around the pipe, has the water just eaten away the glue?

The black pipe goes to a new pipe that was installed outside, it runs at a 45 degree angle down to the drain. I have looked down the outside pipe and it is clear. I can't get a close up picture at the minute as it is too dark.

ThisIsWeird

fossman said:

This is the full pipe on it's way to the wall.

There is not enough play to pull the pipe out of the reducer. How can I tell if they are push-tight rather than solvented?

Where the pipe meets the reducer there does appear to be some "dried glue" marks around the pipe, has the water just eaten away the glue?

The black pipe goes to a new pipe that was installed outside, it runs at a 45 degree angle down to the drain. I have looked down the outside pipe and it is clear. I can't get a close up picture at the minute as it is too dark.

Thanks.
To confirm - is the bottom of the black pipe 'open' above the drain outside - can you see  that the condensate does trickle out?
The two white elbows are, most likely, solvented, so fixed - you might be able to see a ridge of the stuff around each end. Or, possibly only the lower ends are done to make sure they're watertight, but the tops aren't, to allow disassembly - hard to know. But if you grab the bottom elbow firmly, and try and twist the horizontal pipe, you should hopefully see if it's a push-fit only.
You can try this between the two elbows too,  holding the top elbow firmly to prevent any movement transferring to the boiler, and seeing if any joint allows turning movement.
But fair chance it's only detachable where it connects to the syphon trap inside the boiler. Very annoying, as this is usually a simple job that's very DIYable, but the pipe disappears into the boiler!
Have you mentioned the make and model?

Anyway, look very closely at the elbow ends and report back.
See how far you can pull the horiz pipe out of that reducer using the 'flex' in the pipes - 5mm? More?
Make and model of boiler, please.

This can just be sealed off using any number of sealants, but it would be nice to get to the bottom of the issue. We'll guide on a simple method once you report back. (That does not include using solvent, as the reducer is likely 'rubber', so no good.) That white pipe should be a nice snug fit in that rubber reducer, but it looks too loose - there's an obvious gap. 

ThisIsWeird

Ok, to cut to the chase. 
First confirm that the black pipe outside IS draining freely - I think that's important. We need to know the liquid isn't backing up - very unlikely, but trouble if it is!
Then simplest fix is to use Plumber's Mait  - £5 at Screwfix and others - as it's very pushinable and doesn't set. 
Boiler off and cold, so not producing condensate.
Press kitchen paper firmly against the seep and hold - let capillary action draw out the liquid. Gently pull and push the white pipe in and out of the reducer as far as it goes without stressing the elbows - 5 to 10mm? 
The make a thin - 6mm - sausage of the Mait and wrap it around the pipe, gently pull the pipe out, and use a blunt object - flat-blade screwdriver? - to push the mate into the round tiny gap. As you press it in, focussing on the pipe bottom, allow the pipe to spring back to its relaxed position too, and that should help draw the Mait in a few mm further. Finish off my removing the excess Mait, leaving just a 'seal', and not a visual mess!
Other sealants will also do - silicone, Stixall, etc. 
Place newspaper sheet on floor to indicate any further leaks.
Ask plumber to check the actual problem come next service.
But, provided the black pipe is draining fine, this is not a 'problem'. But bear in mind the condensate is slightly acidic, so will stain many materials, and possibly even etch ceramics and stone. Oh, and it'll corrode copper with ease...

fossman

ThisIsWeird said:

Ok, to cut to the chase. 
First confirm that the black pipe outside IS draining freely - I think that's important. We need to know the liquid isn't backing up - very unlikely, but trouble if it is!
Then simplest fix is to use Plumber's Mait  - £5 at Screwfix and others - as it's very pushinable and doesn't set. 
Boiler off and cold, so not producing condensate.
Press kitchen pepper firmly against the seep and hold - let capillary action draw out the liquid. Gently pull and push the white pipe in and out of the reducer as far as it goes without stressing the elbows - 5 to 10mm? 
The make a thin - 6mm - sausage of the Mait and wrap it around the pipe, gently pull the pipe out, and use a blunt object - flat-blade screwdriver? - to push the mate into the round tiny gap. As you press it in, focussing on the pipe bottom, allow the pipe to spring back to its relaxed position too, and that should help draw the Mait in a few mm further. Finish off my removing the excess Mait, leaving just a 'seal', and not a visual mess!
Other sealants will also do - silicone, Stixall, etc. 
Place newspaper sheet on floor to indicate any further leaks.
Ask plumber to check the actual problem come next service.
But, provided the black pipe is draining fine, this is not a 'problem'. But bear in mind the condensate is slightly acidic, so will stain many materials, and possibly even etch ceramics and stone. Oh, and it'll corrode copper with ease...

Sorry I wasn't ignoring your last post I was just waiting until I was home from work before replying.

I have tried pulling and turning the pipes and nothing moves. The pipe going into the reducer has a small amount of movement (say 5mm) but not enough to remove it from the reducer.

The boiler is a Worcester Bosch Greenstar 4000 30kw. The bottom of the outside black pipe is visible so I should be able to see any water coming out into the drain when it is daylight. I will try the Plumbers Mait suggestion.