Saniflo - Waste pipe diameter?

[outmyway]

I'm installing a Saniflo Sanislim macerator -

I'm suprised the main waste outlet is only 22mm diameter ..

Looking at the installation guide its a bit ambigous if I should route this into a 32mm (or 40mm) pipe once it goes 'horizontal' at the top of the vertical ...

Is this the case ... or will running 22mm pipe all the way out to my drain be OK?

Or would it work better if I used 32mm pipe straight out from the unit?

 

[bengasman]

It is not 22, it is overflow pipe.
You can normally keep it in the same size, just reread the manual a couple of times.

 

[outmyway]

Thanks bengasman

Ah yes, found this in the manual ...

Connect the end of the 20/26 discharge hose (G) to the elbow and the other end
to 22mm copper or rigid UPVC pipe and secure with metal hose clips (H).
The discharge hose allows connection to the rigid drain pipe (22/23) without
creating vibration.

I'm surprised 22mm pipe is wide enough .... but gues Saniflo know what they are doing!

Saniflo manual very breif ... just a diagram showing the 22mm verticals feeding into 32 or 40mm horizontals

 

[bengasman]

Most, if not all, saniflo's have a chopper in it that effectively liquefies any solids, and subsequently pumps the lot like water.
Larger bores waste are to allow larger volumes or bits to aquaplane under gravity and as saniflo does not have to bother with either, there is usually no need for more than overflow pipe.
Make sure you identify when you need copper (22mm) and when overflow (21.5).
22, plastic or copper, does not connect easily to 32 or 40 mm, overflow does.
And you need good, solid connections; glue, solvent weld, plastic cement, or whatever you want to call it.
Having a slight drip here or there from clean water is one thing........

Have you ever experienced the difference between jumping with 2 feet in a puddle and doing the same with a fresh cowpat?

 

[Agile]

When I fitted one in my house the instructions were very clear and if I remember only allowed 22 mm up to a rather short distance to the discharge point of about 3m. For longer lengths it was 32 mm.

Its probably rather quieter if 32 mm is used.

I am always surprised that they use such a powerful and noise motor which pumps a toilet discharge of 66-7 litres in about three seconds.

Tony

 

[kirkgas]

a 100% sound way to connect 22mm copper into 32/38 plastic is to use a McAlpine washing machine spigot, cut off the nozzle and screw a 3/4" FI x 22mm brass adaptor onto the thread, fit the nozzle into a 38mm McAlpine straight coupling (with 38x32 reducer in the other end if required)

 

[outmyway]

Total run is less than 3m (about 2.2m vertical and .5 horizontal) ... so I will use 22 all the way to the external drain 40mm.

I've found the 'easy plumb' drain kits (like for washing machines etc) come with lots of adaptors etc ..

But, yeah, trying to find 22mm-> 32/40mm adaptor is not easy .. surpised Saniflo dont include one.

 

[Graeme53]

I am installing an ensuite into a bedroom above our downstairs utility room. I need to use a saniflo for the toilet because there is no 100mm stack pipe above the utilty room or conveniently close to the bedroom. However, I can connect the waste from the sink and shower straight down into a 40mm waste pipe in the corner of the utilty room. Can I also connect the outlet from the saniflo into this 40mm waste pipe? Or do I have to take it up through the loft and about 7 metres along to a 100mm stack pipe above the bathroom? Obviously it would be a lot easier just to connect it into the 40mm waste pipe, if allowed.

 

[outmyway]

Graeme53 - I cant see a problem with that ...

Personally having installed a Saniflo with no option in my basement than to 'pump it up', I would try and avoid using one if their is anyway you could run a 100mm soil waste out to meet your existing stack or ground pipework?

The Saniflo works well, but iit s very noisy and can be heard all throughout the house .... I also live in fear of guests putting things down the toilet they shouldn't!

 

[Hugh Jaleak]

I'd give the Saniflo a dedicated run to the stack. Otherwise you may have a very nasty shock when the Saniflo operates....

 

[Graeme53]

Graeme53 - I cant see a problem with that ...

Personally having installed a Saniflo with no option in my basement than to 'pump it up', I would try and avoid using one if their is anyway you could run a 100mm soil waste out to meet your existing stack or ground pipework?

The Saniflo works well, but iit s very noisy and can be heard all throughout the house .... I also live in fear of guests putting things down the toilet they shouldn't!

Unfortunately there is no ground pipework nearby outside and trying to run it in 100mm waste pipe to conect to the stack would mean running through a conservatory to maintain the gradient, so not really an option! Sounds like running it straight down into the 40mm waste pipe should be OK. I had a look in the building regs for waste pipes, but can't find any reference to using macerators for toilets. Hopefully, the noise of the macerator running should be not too bad as it will only run when the toilet is flushed and the cistern is filling.

 

[Graeme53]

I'd give the Saniflo a dedicated run to the stack. Otherwise you may have a very nasty shock when the Saniflo operates....

If the flow out is straight down the 40mm waste pipe and the shower and sinks have non-return valves in the waste, will that not prevent a nasty shock?

 

[Hugh Jaleak]

Saniflo's pump under high pressure, which is why copper or solvent weld pipework is required on the discharge pipe. It could be possible the pressure created when the unit is operating would be enough to 'blow apart' any compression waste fittings, bearing in mind these are designed to be used at atmospheric pressure.

 

[flameport]

I am installing an ensuite into a bedroom above our downstairs utility room. I need to use a saniflo for the toilet because there is no 100mm stack pipe above the utilty room or conveniently close to the bedroom.

Find somewhere for a normal 100mm waste, or get one put in, or scrap the ensuite idea completely.

Only one thing certain about saniflos - they will break, and when they do, you will wish you had never even heard of them.

Think of a disgusting, vile mess of minced sewage.
Now consider the same in a long length of waste pipe - particularly if the pipe happens to go upwards from the saniflo.
Now consider what happens when that pipe has to be disconnected to repair the saniflo.