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Fitment of a saniflo toilet

what is needed to plumb the waste of a saniflo toilet and how is the connection made to the soil stack pipe?
The toilet is on the ground floor and will
need the waste to flow under kitchen cupboards to the stack pipe in the kitchen

With regards to the toilet pan, is there a specific type that has to be used, or can any pan be connected.

Cheers for the answers, very helpfull :-)

7 Answers from MyBuilder Plumbers

Best Answer

Saniflow pumps typically require a 22mm pipe taken from the unit to the soil stack.

This could be run in flexible p.v.c. pipe such as speed fit or hep20 or in copper.

Utilising plastic pipe may reduce the number of bends required and thus preventing blockages in the future.

If there is a way of increasing the pipe size to 40mm or 32mm, working away from the soil stack, via the kitchen, towards the unit this would enevitably allow the pumb to perform better, though not a requirement.

Saniflows, depending on which model you choose, can be quite happy pumping vertically and horizontally, even with a reduced pipe-work size of 22mm.

As for making into the soil stack, this depends on wheter it is cast iron or Plastic.

Various options are available for each and a good plumbers merchant will advise and supply you the fittings. Cast iron will need to either drilled into and a boss fitted, or a section cut out and replaced with a special rubber connection then converted to plastic.

Plastic soil pipes can be simply drilled and a strap on type outlet fitted, and reducer fitted to pick up your chossen pipe-work size


Answered 18th Mar 2011

Saniflos normally come with an adapter which allows you to alter the pipe size slightly, 22mm copper or 21.5mm overflow pipe will do the job.I would recommend the 21.5mm overflow pipe as solvent weld fittings are both cheap and reliable and easy for diy. if you are joining to a 4" soil stack you will need a 'strap on boss' and '21.5mm boss adapter'. the adapter will be either rubber, or solvent weld. if you can, again i'd recommend the solvent weld version, as the saniflow does pump quite fiercely. Regarding the 4" stack, if it's not plastic, you need to let us know because it's not so straight forward. Only other point to make is read your instructions clearly on pipe sizing, and permissable routes. ie you can run your pipe level for x number of meters, then up y number of meters then needs a continuous flow down to soil stack. You can't run up, then along then down then along then up again. The instructions supplied are pretty comprhensive and self explanatory. Good luck, hope all goes well. Jez

With reference to your question ammendment, regaring pan connection. All toilet pans have the same outlet. The saniflow comes with a rubber bellow type connection with a large jubilee clip, these will all look very obvious when you start to fit it. As for the design of the toilet, you need to remember that the saniflow has to sit behind it. A lot of modern design toilets have a skirted bowl, (where the sides curve out and back to hide the pipework) these wont sit back to the wall with the saniflow in the way. Check the measurements of the saniflow to the spec of the toilet. If you are buying from a large retail diy outlet, or bathroom shop or indeed any plumbers merchants, they will advise you on compatability if you are unsure. Hope this helps


Answered 21st Mar 2011

the saniflo unit normaly has a 32mm outlet, use 32mm waste pipe or similar( blue alkathene water) to route to stack pipe and connect to stack pipe using a strap boss, regards Terry. the type of toilet depends on the siting of the saniflo unit,a straight outlet is required if the unit is mounted directly behind the toilet at floor level but check that the outlet height matches with saniflo, you may have to pack saniflo to match. a bent outlet would only be used if saniflo is sited below floor level.regards Terry


Answered 20th Mar 2011

The waste from a saniflo can be either 32mm or 40mm as the waste connector on the top of the saniflo can be cut to whichever size. You are reccomended not to use 90 deg bends to aid flow if a bend is needed use 2x45 deg bends to form a swept bend. To connect to the soil stack you will need a boss adaptor, drill a hole in the stack and glue/tighten the boss to it and you have the connection for your wast pipe. hope this helps!


Answered 18th Mar 2011

You would need a 4" strap on boss with the right fitting to take the size pipe you are running from the saniflo the correct. You would need to drill the correct size hole in the soil pipe then fit the strap on boss with glue and leave to set before fitting pipework.


Answered 18th Mar 2011

It all depends on the size of waste pipe required by the supplier of the Saniflow, generally all you need is a power supply and a cold water inlet. The waste is normally made into the cut out of a branch in the SVP. If there is no branch at ground level where u need to be, then look at a solvent glue on, strap on boss, cut the pipe glue and strap on the boss, let it harden then fit the required waste pipe into the boss with any adaptors. Remember Saniflows are no where near as good as full 110mm drains, They have to macerate and pump waste to the drains.
Research it first are u sure you can't get into the sewerage system? regards Mark


Answered 18th Mar 2011

You will need cold feed supply to toilet cistern, a Rcd covered switched fused spur point for the saniflo.
You will then need to use solvent weld piping and try to use as little bends (elbows) as possible, connection to soil stack (plastic) is made with a strap on boss(I know) a hole being drilled and then the boss solvent welded on.
Fairly straight foward job, just make sure all connections are good as you dont want any leaks!!


Answered 18th Mar 2011

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