How to install a Macerator

[Stephen Rann]

Hi folks .. looking to install a macerator for someone, Advise on discharge pipe please .. presume 32mm same as sink waste ?? and what fall is required on this ? TIA

 

[Newboy]

Discharge pipework size varies by model and manufacturer.

Total distance, max. lift and fall likewise

MI's would be a good place to start!

 

[oldbutnotdead]

Don't do it- they're expensive, noisy and unreliable.

 

[mattylad]

Standard installations are as follows:

Put the macerator in the room it is intended to fit it in.
Add high explosives, petrol and other flammable materials.
Light a match, drop it on it and run - never go back to that house.

Mine is old, not too noisy and works every time.

Since the nightmare of fixing the non return valve, stripping the unit down and cleaning it, getting covered in ****e from various people, never using the downstairs toilet again....

 

[durhamplumber]

Don't do it- they're expensive, noisy and unreliable.

Install it in the bin,save yourself a world of trouble diggin around in pressurrised sht...It WILL block.

 

[Hugh Jaleak]

If there is absolutely no other option, then fit one, but there must be another WC in the property. Secondly, apart from toilet tissue, nothing is to go through it that hasn't been through you first. Thirdly, manufacturers instructions override everything else. Any upwards run of the discharge pipework must be immediately after leaving the unit, and then a sensible fall for the rest of the distance to the stack.

 

[Mottie]

We have one in our downstairs loo. Decided on that rather than the expense of getting a main drain from the front of our house to the back and breaking into the sewer. I have a Saniflo Sani-slim which can take a WC, a basin and a shower. It has packed up twice in the 15 or so years we've had it. First time after about 5 years I just replaced it, cost about £300, second time I chucked a wodge of non-chopppable tissue down it and jammed it up. With the help of 'just pumps' on this forum, I fixed it with a £5 capacitor. Wifey insists it’s for number ones only but I ignore that instruction if she’s out. As long as you stick to the three 'P's' - P iss, Poo and Paper it should be fine.

I have ours boxed in with some sound deadening inside the box so it’s very quiet - in fact the flush and the water refilling it totally drown out the sound of the macerator.

 

[muggles]

Detailed info here

 

[just pumps]

Detailed info here

Really?! This old mis-guided item again.
So full of errors re the installation.
So out of date now, talk about how to mis-inform people.

 

[mattylad]

I would say though, if your installing one that AFAIK and through personal experience that the non return valve is something that can fail.
It can be cleaned, sometimes you can get replacements but as years go by they can be harder to get as the model goes obsolete.

So it may be a good idea to leave enough vertical piping accessible that you can fit an external non return valve on.
Like this one.

Mine is fitted using 32mm ish solvent piping which goes horizontal for 12" then up for 3', at an angle for about 4' more then about 15' horizontal through the house to the downpipe out back.
It works.

It got blocked up many years ago and was just ignored for a few years until I gathered up enough courage to take it out back, take it apart and clean it out.
Removing the damn wet wipes that had clogged it up, then banning thier use in the downstairs loo it got refitted and the only problem was the NRV.
With that sorted it has had occasional use (this actually reminds me to clear the downstairs loo out of the crud thats filling it this week while I have time).

My dad had one, it worked then too.
They do until they do not - a bit like everything else really.
It's just that these are a shi tty thing to work on when they do not.

A written sign about "Do not put anything in me unless it has been through you!" is a good idea.

 

[dilalio]

Secondly, apart from toilet tissue, nothing is to go through it that hasn't been through you first.

A written sign about "Do not put anything in me unless it has been through you!" is a good idea.

Exactly what I said to a customer about 10 years ago having found olive stones/pits blocking her macerator... She went very red and informed me that her son eats olives... and swallows the stones/pits

 

[HERTS P&D]

The 3 P's:

Pee, Poo and Paper.

Andy

 

[dilalio]

The 3 P's:

Pee, Poo and Paper.

Andy

4 p's?
Puke?

 

[durhamplumber]

4 p's?
Puke?

Lol...when you unblock them..

 

[Hugh Jaleak]

Dont recommend testing with puke. I fitted (under protest) a replacement macerator for a friend of a friend a couple of years back. It was one of those jobs where you get a huge sense of deja vu, small WC compartment under the stairs, in a particular street. It turned out, they also knew someone I used to know, and my former acquaintance had dragged me round to their house a few years previously to look at a 'blocked toilet' after his dear (now ex) wife, had got herself plastered, honked her guts up and blocked said WC. I took one look and realised what the issue was, and politely declined any further involvement.

Pretty sure it hadn't worked after then until I fitted the new unit, a number of years later.