Condensate pipe help needed please

PJ_queen

So my boiler is in the middle of the house and condensate pipe goes out onto flat roof. As my flat roof is rubberized I don’t want the slightly alkaline condensate pooling on the rubber so it goes along the wall and onto downpipe. This run is about 8 feet.

about once a year it freezes which is a pain as it switches boiler off and every year I tell my self to sort it and now I am trying to.

This pipe is 22mm diameter and as the hole to the inside is fairly low it doesn’t have much fall on it which again doesn’t help with freezing.

if I somehow change the pipe to 32 mm will this maybe cure the freezing? Failing that as I have an upstanding on the edge of my roof my other brill idea was to run the pipe sort of diagonally across the roof so the condensate falls directly into a downpipe which will make the fall a bit better. I have been to b and an and screw fix to find  a push fit connection which will do this diagonal 45  degree angle but they don’t do it. 

I admit to being very diy challenged but would welcome any suggestions. 

WIAWSNB

Yes, a larger pipe should help it drain away more quickly. Coupled with the best fall you can possibly give it - so the condie doesn't hang around inside the pipe - and finally with added insulation, so the warm condie can hopefully get to the end before it freezes

Where does it currently end up? The slightly acidic condie isn't good with concrete and brick and stuff like that, so best check that the new end point is going to be happy to receive it.

A photo would help us understand what's going on.

daveyjp

Condensate is acidic, not alkaline, but if it runs into a drain thats fine.  45 degree 22mm upvc angles are available online if you can't get one locally.  To prevent freezing use pipe lagging.

Mr.Generous

Lagging won't help much, If I had a condensate pipe in a very exposed place likely to freeze and difficult to defrost - ie not at ground level, then I'd run a small bore pipe inside a 40mm pipe for double skin insulation.

greyteam1959

Can you not plumb the condensate pipe into your sink or bath waste pipe ??
That would solve your problem.

chris_n

Mr.Generous said:

Lagging won't help much, If I had a condensate pipe in a very exposed place likely to freeze and difficult to defrost - ie not at ground level, then I'd run a small bore pipe inside a 40mm pipe for double skin insulation.

In the first instance that is what I would do if I lived there, or better still if it was a rental use trace heating on the inner pipe (I don't live in UK but my daughter rents from me, the current boiler isn't condensing but if it was then that would be my preferred choice )

PJ_queen

Thanks for your comments. I will try to get a quote for it to be directed straight to my waste if I can get someone. I have tried Checkatrade in the past and no one ever contacted me lol.

i have attached a photo to show. The pipes a bit wobbly as I have unhooked it from wall but where it currently is it has to go over the 4inch upstanding I have round the flat roof but if I can get it to go diagonally it can go down the overflow/downpipe which goes off that side of the flat roof at the bottom of the upstanding bit so the fall is better

TELLIT01

Even the section where the clip hasn't been removed sags.  That's where the water will build up and freeze.  Lagging will make very little difference in my experience.  When our boiler was installed the condensate pipe ran the length of a flat roof, along a north facing wall, and it froze regularly.  We managed to get most of the pipe reroute inside the house by adding trunking.  There was then only a vertical drop outside directly into a drain.

Albermarle

We have a more vertical drop and it has only frozen once in about 8 years, although we do not live in a particularly cold area.

WIAWSNB

PJ_queen said:

Blimey. I know you said that the sagging is greater since it's been unclipped, but I think it's clear that any sagging over such a low fall would cause issues; the condie will settle in the dips, and hence freeze very easily.

Has even the wrong pipe been used? It should be 'rigid' 22mm pipe, as used for tank overflows.

What actual 'fall' do you have available there, and over what distance? If you can tell us this, then we should be able to figure out whether a method of keeping it straight - at a slope - should do. Other wise, change its direction as you said, if it gets you the required fall.

And pipe lagging will help. And/or, change to a larger bore pipe as you suggested.

jefaz07

WIAWSNB said:

PJ_queen said:

Blimey. I know you said that the sagging is greater since it's been unclipped, but I think it's clear that any sagging over such a low fall would cause issues; the condie will settle in the dips, and hence freeze very easily.

Has even the wrong pipe been used? It should be 'rigid' 22mm pipe, as used for tank overflows.

What actual 'fall' do you have available there, and over what distance? If you can tell us this, then we should be able to figure out whether a method of keeping it straight - at a slope - should do. Other wise, change its direction as you said, if it gets you the required fall.

And pipe lagging will help. And/or, change to a larger bore pipe as you suggested.

Overflow is actually 21.5mm. I have no idea what that is, but possibly, it has frozen before or blocked somewhere so someone has cut it to drain where it is out of the clip. 

I’d be looking at installing 1” 1/2 with a fall. 

Can a condensate pump be used to take it to a different waste? 

If you’re going to lag it, look at armaflex lagging. It’s what I use if I have to.