Condensation pipe size/material

[Dan the plumber]

Evening all,Bit of advice needed if poss; Currently doing a bathroom refurb & took the bath out today to discover the condensation pipe has been ran behind the bath in 15mm copper (bout 12ft of it as the airing cupboard is in the middle of the house!). The problem is I'm installing a shower cubicle on the same wall=will it be ok to rerun the pipe under the floor in poly then switch to copper externally!? Will 15mm be ok or should I upsize to 22mm!? Also, does it have to be solvent weld or will push fit suffice!? Thanks in advance for your help all

 

[Bartdude]

Do you mean a condense pipe from a boiler? If so it shouldn't be copper,condensate will eat through that.It should be solvent weld plastic.

 

[diamondgas]

Sure its the condensate nd not the safety blow-off pipe?

 

[Dan the plumber]

Yes sorry, a condense pipe is what I meant! It's from a Worcester combi boiler and think the label referring to the pipe work under boiler read "safety device" and terminates outside as a usual condense pipe does! Should I change the complete pipe run to solvent weld then!? Just out of interest, is it a big no no to run a condense pipe in poly push fit!? Just thinking out loud as will need to go through approx 15 joists and with poly would make life allot easier!

 

[diamondgas]

Dan do you know any gas safe engineers? Sounds like you're talking about PRV pipe but describing it as condensate ... Totally different my friend!

 

[Dan the plumber]

"Sure its the condensate nd not the safety blow-off pipe?" Steve you could be right as label does read "safety device" from memory!? How does this differ from a condense pipe!!? There is only 1 pipe that exits the property & this is that pipe!? Sorry if the above is a bit of a "fick" question.....gas is next on the adgender, when funds allow!!!!

 

[diamondgas]

sounds like you may have a none condensing boiler Dan if theres only one pipe leaving the boiler and venturing outside or to a waste pipe...
If that's the case you can re-route the pipe under floorboards to outside but should be falling all the way, copper I believe ... did all mine in copper anyhow!

 

[Dan the plumber]

Steve thanks for your help mate, appreciate it. Would it be wrong if I substituted copper for poly or is this a no go!? Running a 12ft length of rigid copper through 15 or so joists...and at a constant fall!!!!!!! I ain't looking forward to that task :-/ lol

 

[GQuigley67]

it will be water at 95 degrees if it ever did blow off, which would melt plastic so no. Is it not close to an outside wall where you can re-route it straight out the wall ??

 

[Dan the plumber]

it will be water at 95 degrees if it ever did blow off, which would melt plastic so no. Is it not close to an outside wall where you can re-route it straight out the wall ??

Unfortunately not, airing cupboard is middle of the house and is a terraced house so no external wall behind boiler either!Only other option would be to take it the other way into the bedroom & exit external wall at rear of property! What deg should the fall be!?

 

[GQuigley67]

you could discharge it into waste pipe via a tundish so it has an air break, are you able to do that ?

 

[diamondgas]

Well dan don't worry to much about a fall! as long as it isn't gonna trap water on it's way out, end of the day there's gonna be 3Bar pressure behind it worse case scenario .. I'm not up on heat carrying capacity of plastic pipe .. check out manufacturers info ... someone here might know the ins and outs ...

 

[Dan the plumber]

you could discharge it into waste pipe via a tundish so it has an air break, are you able to do that ?

Not really as the closest waste typically will be the shower waste and this will have to be run above board level as part of old style cast waste stack set up is installed!!!Guess I could possibly run the pipe downstairs then exit from there!?

 

[GQuigley67]

best checking out if you can use plastic pipe, I'm not too sure as I think you would need an air break before going to plastic.

 

[cjg]

prv should be run in copper all the way out and terminated on a u/bend or the new cowl fitting, under no circumstance should it run in plastic