Kitchen sink waste-boiler waste connection

Discussion in 'Plumbers' Talk' started by do224, Aug 2, 2015.

  1. do224

    do224 Member

    Hello,

    I'm currently installing a new kitchen in my flat and I'm struggling to work out which connections I need under the sink (it's a 1 1/2 bowl). I've had a new combi boiler installed which has a waste pipe running under the floor and popping up under the sink (condensate?). The installer said to connect it to the sink trap. I've also got a washer dryer that will be connected to the trap.

    I think the Mcalpine SK1a or SSK2 would work? But how do I connect the condensate pipe to the trap (see pic).

    If anyone can shed any light on this I would be very grateful!

    Thanks, David
     

    Attached Files:

  2. Doesn't the sink come with a trap? If it does, it's likely to have at least one 'hose' connector already on it, perhaps even two.

    That clear pipe, is that the condensate pipe? I've never seen one like that - I'm only familiar with rigid plastic pipe, or 22mm size.

    Anyways, perhaps technology has passed me by, but if that is the condensate pipe then it looks as tho' it's designed for pushing straight on to a W/M style fitting like on the two McAlpine wastes you linked to.

    A concern, tho' - these condensate pipes surely need to have a steady fall on them all the way to the waste connector. How can you guarantee that with a flexible pipe?

    But, assuming that is a legit condensate pipe, and a fall is assured, then it's surely chust designed to push on.

    If you also have a W/M to fit, chose a waste system with provision for two of them pushy thingies (assuming the W/M is going to be sited close to the sink?)

    (That white connector in your pic - that usually fits straight in to a removable cap on the McAlipne (and other...) wastes. You unscrew the cap, push out the sealing disc sat in it, insert that white spigot, and replace. Then push the hose onski.)
     
  3. do224

    do224 Member

    Thanks for the reply. The pipe runs from a pump so presumably doesn't need a fall? I've taken another pic of the pipe and fitting next to a washing machine connector. The pipe is too narrow to push directly on as you can see and the fitting won't push on/in either as it is the same size as the connector. What am I missing......I'm sure there must be a simple solution?
     

    Attached Files:

  4. CGN

    CGN Screwfix Select

  5. do224

    do224 Member

    Hi CGN,

    I'm not with you....that's just a standard hose connector isn't it-like the one in the picture I posted above? Neither the transparent pipe nor the fitting supplied with it will fit directly on to one of those. Thats the problem
     
  6. CGN

    CGN Screwfix Select

    Too small a bore?! Ok, can you increase bore of condensate to fit onto a spigot of that size? I'm working on a property at mo and condensate is piped in rigid plastic overflow into a tee connected to 40mm waste.
     
  7. nigel willson

    nigel willson Screwfix Select

    As I see it, can you 1. Cut off first bit of washing machine spigot and fit the other bit into it or 2. Use o rubber coupler like you get with some dishwashers to connect wast up.
     
  8. KIAB

    KIAB Super Member

    No idea what trap you have, but there is andaptor for traps, Mcalpine R16 1ΒΌ" x 19/23mm, you can remove wm spigot & use this in it's place. Might work?

    upload_2015-8-2_20-29-4.jpeg


    You also need a nonreturn valve R14 to stop sink water flowing back into your boiler.
     
    Last edited: Aug 2, 2015
  9. Ah, a pumped supply - that explains things.

    (I presume there is no easy way for the boiler condensate to 'fall' to the waste pipe under gravity? Using a pump is a last resort, usually.)

    Anyways, see that waste fitting you have in that picture - I mean the main one on the right, the one that's part of your sink waste system? Ok, if you look at it you'll see it's made up of two increasing diameters of push-fit end to take a hose? Yes? And then you'll see it actually has a threaded part?

    Ok, I'm pretty sure - tho' not 100% certain - that this is what ye do; if yer hose fits on the narrowest part, then you push on yer 'ose. Jobbie jobbed. If the hose is too big for that end but suits the wider spigot, then you cut off the narrow bit and throw it away. Jobbie jobbed.

    Ok, what you'll have to do is to cut off both hose push parts to leave chust the threaded collar. You then rummage amongst the parts that came with your sink's waste to find a holed cap that'll screw on to this part. But first you push in that other spigot/connector that you have in to the waste and screw the holed collar over it to secure it in place.

    The clear plastic pipe will then push on to that wee spigot. Jobbie jobbed.

    (Now you're going to tell me there's no screwed cap/collar in the parts bag?)
     
  10. do224

    do224 Member

    KIAB, thanks-that adaptor looks like it may work. I've got a non-return valve, it's the small white connector in the first pic. I thought it was just a straight connector but you can only blow through it one way.

    Devil's advocate, thanks that also seems a possible solution. I haven't bought the trap yet, the waste fitting in the pic was taken off another sink for purposes of the picture. Is it likely there will be a holed screw cap in the pack when I buy it. I'm intending to buy the Mcalpine SSK2 double bowl trap (as nowhere has the SK1A in stock which is a 1 and a half bowl kit).

    Presumably the 2 bowl trap will be fine for a 1 1/2 bowl sink?

    Thanks
     
  11. KIAB

    KIAB Super Member

    SK1A is a stock item in Plumcentre, but they will screw you on the price most likely.

    Plenty on Ebay

    You can shorten the pipes on the SSK2 I think, so it's not so intrusive in the cupboard, BUT you going to come unstuck I think, as the half bowl is a different depth.

    SK1A below.



    [​IMG]
     
    Last edited: Aug 3, 2015
  12. do224

    do224 Member

    Could you not just cut the pipes down to fit if using the SSK2 on a 1 1/2 bowl sink?

    I've tried removing the small hose connector on another sink and putting the adaptor straight in then using the collar to tighten but the collar has a larger diameter opening than the adaptor so adaptor isn't held in place-it can just be pulled back through the collar (see pic). The none return valve is tiny (see pic in my first post)
     

    Attached Files:

  13. do224

    do224 Member

    OK, I've ordered a Mcalpine SK1a (they were out of stock at local PlumbCenter and it was half the price on ebay anyway). I think one or other of the suggestions mentioned is likely to work (fingers crossed) so thanks very much.

    My only remaining concern is whether it is OK to connect the condensate discharge above the U bend. I've read that in some cases the boiler can release combustion gases such as carbon monoxide via the condensate pipe. If this was to happen then wouldn't these gases come up through the kitchen sink and into the house if the the connection is above the U bend?
     
  14. I'm hopeful that the MA15 nozzles as shown in the line diagram above will be smaller than that other screw-capped fitting you've tried, so will do the job you want.

    But I could be wrong...
     
  15. do224

    do224 Member

    Thanks for the advice. I bought an R16 adaptor and took the collar and rubber ring from it. I removed washing machine spigot and replaced with R16 rubber ring and my condensate pipe fitting and used R16 collar to hold in place.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice