condensate pipe into internal waste

We are re arranging our bathroom to fit a shower cubicle in, and will be putting the basin waste under the floor in 36mm plastic weld. we had thought about putting the basin waste into 40mm pipe then running the condensate pipe into that ( under the bathroom floor).

Thats a good idea and there is no problems with doing that. Fit a HepVo trap inline before the condendse pipe joins the waste and you will have no problems.

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Hey i felt the need to add to this thread.

I have a Worcester Bosch 35 CDI i think it is and its been installed for 34 years and at the end of last winter i had a frozen condensate pipe. Ater defrosting the system which was 32mm i reworked it to increase the drop and slope it falls at and then lagged it with some armoflex i think its called.

Come this winter....

My pipe now freezes on a daily basis and its now lagged 32mm and ive had to add points of entry to add hot water to defrost the inside of the pipe. Its getting that bad now (and were not in winter yet) im looking at re working the pipe to indoors and running into the bathroom. We are getting low temps around here which is colder than normal of down to -10 most nights. I even bought a thermometer probe to measure the temperature of inside the pipe and it frequently drops below 0.

I can tap into the condensate pipe internally without touching the boiler so thats ok but is there guidance of where i need to put it into ie soil pipe etc?

Im aware i need to use solvent pipes and the fall needs to be sufficient enough to allow for smooth running. Is there anything else i would nee to consider? What about the diameter of the pipe for internal use i know WB suggest 32mm for external use what about internal?

How about Armaflex insulation :idea: could be waterproof - and if it`s not it can be covered with butyl sheet - Damp insulation is no insulation
Anyway you aren't alone. Put it down to freak conditions. Haven't had this problem since condensing came out en mass 5 or so years ago, therefore very freak circumstances which cannot be designed for.

Global warming :rolleyes:

Err, no. Freezing temperatures, like the past two years, are normal in winter in the UK. It was the unseasonably warm winter weather that we had for the 5 or so years prior to that which were abnormal.

Water freezes at 0 degC; simples. What is really amazing is the number of simpleton installers and householders who have been surprised by this.

There are a lot of people talking a lot of [email protected]@cks here.

The start of this year saw the worst winter conditions for around 50 years and we are now currently experiencing one of the coldest UK winters since records began - - it is almost certain that it will be the coldest December on record - period! I'm no fan of the Daily Mail but they are using scientific data on this one, not just right wing narrow minded hyperbole like most of their articles.

So NO THESE TEMPERATURES ARE NOT NORMAL FOR THE UK, certainly not in the last couple of hundred years.

Secondly if its so plain and simple that water freezes at 0c and this is normal why has the entire gas industy ripped us all off by installing these combi boilers and condensate pipes that will inevitably freeze in our "normal" winters. Having a heating system that discharges water externally into a thin plastic pipe in -10c and expecting it not to freeze is not reasonable, hence these things are actually unfit for purpose, otherwise there wouldn't be so many people experiencing this issue.
The vast majority of condensate pipes are set up like this, not with frost detection systems and so on.

Finally I fail to see how run off would help, icicles form vertically, if its cold enough where the pipe is running then the angle matters not one jot, in fact it is more likely that the water being spread over an incline out will run thinner and therefore lose any heat quicker making it more likely to freeze, when this happens any flow over it will also freeze and ice will build up - also inevitable.

Ice forms at 0c, who gives a toss if it crystalizes at 3 or 4c its -10c outside, whats the purpose of that discussion?
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...Secondly if its so plain and simple that water freezes at 0c and this is normal why has the entire gas industy ripped us all off by installing these combi boilers and condensate pipes that will inevitably freeze in our "normal" winters...

Very simple answer to that one.
Because the previous Labour government made it law.

Apart from that, out of all the steamers I have installed, only 2 had a pipe frozen. Both times because I did not quite do it as it should have been done. After I corrected my error, both boilers have been working fine.

Condensate pipes do not inevitably freeze. They have been common place on the continent for decades, and nobody there gets upset by temperatures of minus 10 to minus 20.

You are tooting about a subject you know very little about.

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