Grundfoss macerator discharge problem

[Beboers]

Hi Guys,

i fitted a grundfoss solo lift macerator today and ran the dischargein 21.5 mm overflow, I tested it at the end of the day and was getting a couple of drips out of a few of the fittings? Is this just my error in gluing them or should I not have used the solvent weld pipe work and fittings? Appreciate any replies?

 

[lame plumber]

mmmmmmmmmmmmmmm overflow and :001_9898: dont go together in my opinion

 

[Beboers]

Ok what would you have used? 22mm copper? How do you join that to a strap on boss at the stack end? Thanks

 

[lame plumber]

22mm barrier pipe in one complete length via strap on boss and rubber insert in the past, means you can blow through any blockages and no leaks or 11/4" waste works ok as well as long as you glue it properly.

 

[Beboers]

Ok thanks for that lame, I was sure overflow was ok but I suppose I should have checked! Can't really use 22barrier as its all a bit tight for curving it around bends.

 

[Beboers]

Anybody else know anything about running it in 21.5 mm pipe?

 

[Pipes Plumbing]

If it has lots of bends that are too tight to bet barrier bent round, and needs 21.5 elbows you might have fun with blockages...
Also standard solvent weld isn't rated for pressure use, and that's probably what it's getting subjected to if the discharge run has a lot of restriction downstream of the pump.

 

[Mike Jackson]

On the rare occasion I've ever fitted a macerator I've always used 22mm copper with swept bends for the vertical and gone up to 1 1/4 waste for the horizontal.

 

[rpm]

Solvent weld overflow pipe is fine to use on all macerators as the discharge pressure is only around 12 - 15 psi so it sounds like bad joints if their leaking, always use the pipe cleaner on the pipe and the elbow joints before the solvent weld and you should be ok.

Mike is correct in saying the best way to run the pipe is 21.5 / 22mm for the vertical then you can run 32 or 40mm to the stack but the all important factors are the 1:100 (10mm per metre) "fall" on the pipe to the stack and never use sharp 90 degree elbows anywhere.

 

[rpm]

Ps.
If you use solvent weld or barrier pipe or any "pipe on a roll" you have to support it at regular intervals to make sure there are no dips or sags in the pipe when installed or in years to come otherwise water lies in the dips which reduces the full flow of the next lot of water comming along.