condensation pipe keep freezing!

[Jupiter01]

I suspect that this is bad practice but my plumber has my boiler condense pipe terminating into an external drain. This is a ~1cm pipe which comes out of the house and travels around 2 metres along the external wall before it drops into the drain. This freezes in the winter and causes the boiler to fail.

We then pour hot water over it to get things working again. I need to protect this against freezing and was thinking of using pipe lag. Can you please confirm if this will help or provide any other suggestions.

 

[MeldrewsMate]

Lagging will help, but better is to chop the small pipe off as it exits the building to introduce an air break. Then have the end of the smaller pipe dip into a larger pipe (32mm?) which is lagged/insulatedto take the condensate to the drain.
Beyond this there are heated wires which can prevent the freezing you describe, but if you do as above it should not freeze apart from in the most extreme UK winters.

 

[Jupiter01]

That’s a very good suggestion. Thanks! Will the pipe lag slot over a 32mm pipe or should I go smaller? Also, how much of the old pipe needs to be stuck down this new pipe?

 

[durhamplumber]

This is a ~1cm pipe which comes out of the house

Is that a typing error?..Should leave boiler at 22mm diameter and change to 32mm as it exits building

 

[Jupiter01]

No. Its a clear pipe which I would estimate at around 1cm in diameter. Definitely not 22mm. It runs off a Baxi back boiler is that helps/makes a difference.

 

[Harry Bloomfield]

The idea of a large diameter pipe, is that even if it freezes in the pipe, it will take a long time to fill the entire pipe up with a plug of ice. The 1cm pipe just seems wrong, but a few inches of the pipe going into the larger pipe will be enough. The condensate pipe coming out of my Vaillant is a flexible of around 25mm ID, that then goes to a 32mm sloping pipe to drain.

 

[ianmcd]

The clear pipe that you refer to is the pipe that comes with the condensate pump and is not suitable to be used outside

 

[Jupiter01]

Thanks guys. Am I okay to follow @Harry Bloomfield suggestion to pop the existing pipe into a plastic pipe outdoors and then lag this?

 

[ianmcd]

Thanks guys. Am I okay to follow @Harry Bloomfield suggestion to pop the existing pipe into a plastic pipe outdoors and then lag this?

yes that will work but make sure you use waterproof lagging

 

[Jupiter01]

Didn't know there was such a thing! Thanks @ianmcd.

Just wrapping all of this together:
- I can use this for the external drop. Around 2m: https://www.screwfix.com/p/floplast-solvent-weld-waste-pipe-white-32mm-x-3m/61967
- I will cut the existing condense pipe a few inches from teh wall and then shove it into the plastic pipe above
- Insulate the plastic pipe with waterproof insulation. Any suggestions on where I purchase this stuff please?

Also, one other bit of detail: what do I do about the corner where the existing pipe comes out of the wall and bends into the white pipe?

Thanks for your help.

 

[Jupiter01]

Hi Guys, can someone please provide a steer on the above please? I would like to tackle this tomorrow. Thanks again

 

[dilalio]

Some useful info in this...

https://www.google.com/url?sa=t&sou...FjASegQIARAB&usg=AOvVaw2R4lfzAGMzvtH5sGrtzthD

 

[JohnD]

Armaflex make a closed-cell synthetic rubber insulation suitable for outdoor and underground work, but apparently there are two or more grades.

I got mine from a plumbers merchant when doing some blue waterpipe.

They have a website somewhere, but perhaps someone will explain on here.

In my own house I took great care to have the condensate running indoors and connecting to the indoor soil stack, and had the new boiler positioned next to it.

I am a householder not a plumber.

 

[FiremanT]

Hi Guys, can someone please provide a steer on the above please? I would like to tackle this tomorrow. Thanks again

The correct method is to connect the thin pipe to 32 or 40mm INSIDE the property. Then run the larger pipe through the wall.

 

[ianmcd]

As @FiremanT says above you should connect the condensate pump hose to 32 mm and put 32mm through the wall and then down to the drain and lag everything outside, if you are going to do it, do it right the first time