Re-routing condensate pipe

Honeybun · Oct 25, 2011

Like many others my condensate pipe from my boiler repeatedly froze last winter. I have been advised to re-route the pipe so that it remains inside the house. I have a sink adjacent to the boiler and intend to connect the condensate pipe to the waste pipe from the sink, a distance of about 2 meters. This will mean drilling a hole in the work top and feeding the pipe under and across to meet the sink waste outlet pipe.
Is this a good idea, and is there anything I should know or do before I start?

justalex81 · Oct 25, 2011

would it be easier to increase the condense pipe size to 1 1/4" through to outside so it's big enough to not freeze?
failing that not alot to know apart from to make sure there's a fall on the pipe :cheesy:

Halesowen1 · Oct 25, 2011

Increasing the size wont really help, I went out to loads of boilers last winter with 32mm pipe that had still froze.
Run it internal as you say, either cut in a tee with a reducing bung for condense or buy a mcalpine clamp for the pipe.

Halesowen1 · Oct 25, 2011

I use these a lot, you can clamp this to 1.25 or 1.5" pipe, push fit or solder it will seal to anything. Clamp it on then drill a hole into the pipe, about 10-15mm is fine. Its a nice easy and neat job with these.

1¼"/1½" Pipe Clamp (Grey) - Condensate Fittings - Traps | McAlpine Plumbing Products

gornsgorns · Oct 26, 2011

It should be 32mm outside anyway so you can't really increase the size outside. I'd definitely re-route it inside, will save you a lot of worry about it freezing during winter. Why didn't they run it internally in the first place though if it was so close to a sink?