Saniflo (Sanicompact) rough in

[Shawnv92]

I am in the process of converting a laundry room to a half bathroom. The house is on slab, so I have decided to go with a Saniflo unit as I don't want to break into the slab. Specifically the Sanicompact (which is there all in one macerator unit), since the room I'm converting is also kind of small.

Since this is a laundry room, I do have access to a 2" drain pipe, which I plan to tie into. I had a few questions on the rough in for the Saniflo unit for anyone who may be familiar.

1) Standard ABS / PVC DWV systems are rated for 5 psi. Given that the Saniflo has a pump, is it acceptable/safe to connect at grade to the drain pipe without a vertical lift (which would dissipate some of the output pressure). (Such as the drawing A below. Or is it recommended to have some vertical lift (such as drawing B) and if so, what would this minimum lift be. Looking at the output specs of the Sanicompact, it's rated for a vertical lift of 9 ft, which converting to psi puts it right around 5psi for a 9ft high water column, so I'm thinking it should be safe to use this without a vertical lift. Is this correct?

2) When connecting into a vertical drain pipe servicing multiple fixtures (such as wash basin + saniflo), is it recommended to have the saniflo connect above (drawing C) or below (drawing D) the wash-basin (I plan to directly connect the wash basin to my drain stack and not use the wash-basin port on the sanicompact). I'm worried about the saniflo pump shooting waste into the washbasin horizontal run in C, so am thinking D would be better (although I'd be using a sweep tee to make the saniflo connection, so it's unlikely that the flow should enter into the horizontal run for the basin with C, but since it involves poop pumped around with pressure, better to be safe than sorry).

 

[JoeJee]

I used schedule 40 when I did mine. No reason to go with cheap stuff on this. You will need to run a vent to the toilet too. As for the rest, I couldn’t say.

 

[Sponsor]

 

[Tuttles Revenge]

Just a quick look at the instructions indicate that the discharge should rise vertically before travelling horizontally. in fact they state this 2x in their instructions.

Size of the pipe receiving the discharge is determined by the GPM of the pump discharge rate.

Generally a pump wants to be the last fixture in a system.. So most downstream would be preferred.

 

[Shawnv92]

I used schedule 40 when I did mine. No reason to go with cheap stuff on this. You will need to run a vent to the toilet too. As for the rest, I couldn’t say.

I am using schedule 40 PVC for discharge from the Saniflo as well. But at some point the PVC line needs to connect to a standard drain stack, which in my case is ABS rated at 5 psi. Hence wondering if this is a problem or not.

Just a quick look at the instructions indicate that the discharge should rise vertically before travelling horizontally. in fact they state this 2x in their instructions.

Size of the pipe receiving the discharge is determined by the GPM of the pump discharge rate.

Generally a pump wants to be the last fixture in a system.. So most downstream would be preferred.

I believe when they say discharge should rise vertically before horizontally, they mean to avoid long horizontal runs before vertical. No where do they state that horizontal only runs are not allowed. In the installation instructions, they do show an example of a horizontal only run (diagram 5e on page 3 in this link). I have reached out to the manufacturer for clarification as well. I am trying to avoid any unnecessary vertical lifts/turns as I am afraid of clogs in the system.

http://pdf.lowes.com/installationguides/859925002237_install.pdf

 

[Tuttles Revenge]

I looked up their instructions directly from their website. You are correct that the discharge can travel horizontally only. Your D diagram would fit that.

https://www.saniflo.com/us/installing-a-toilet/75-sanicompact-comfort.html

 

[Shawnv92]

I looked up their instructions directly from their website. You are correct that the discharge can travel horizontally only. Your D diagram would fit that.

https://www.saniflo.com/us/installing-a-toilet/75-sanicompact-comfort.html

Thanks! Do you think there's a big difference between C and D from a ease of flow/clogging perspective (when the vertical rise is small, say ~3 ft)?

I like D as I want to minimize the waste travel in the 1" pipework, but the existing layout of pipes and electrical makes C easier. The saniflo pipe needs to run to the right from the drain stack, but there is a rigid conduit getting in the way. I should just be able to wedge in the pipe between the drywall and the conduit, but this doesn't look good. C on the other hand gets cleanly routed over the j-box (the dryer socket is going away, but the j-box stays, as there's some other connections). But if C is more likely to get clogged/suffer from backflow issues, I'd rather go with the ugly install and do D. It's really a question of how good the Saniflo really is at pumping waste through these small pipes vs what they advertise, and TBH I'm unsure at this point.

 

[Tuttles Revenge]

You could shorten the conduit or replace that vertical rigid section with flexible steel conduit and then the 2 pipes could easily pass each other.

I wouldn't hesitate to go over the top of that conduit personally. The pipe itself isn't going to clog.

 

[JoeJee]

I am using schedule 40 PVC for discharge from the Saniflo as well. But at some point the PVC line needs to connect to a standard drain stack, which in my case is ABS rated at 5 psi. Hence wondering if this is a problem or not.

then use whatever you need at the stack you are tying into but use 2”. Run it for a foot or more then have the pressurized line run into the larger two inch before it hits the y. Once the discharge leaves the 3/4 or 1” pressurized line into a 2” line it becomes a gravity drain. I would still use sch 40 as far as I could though.

edit: this is how I ran mine. The wet venting of the line probably is a no go by most plumbers but I didn’t have any other way to do it. Works great so far.

 

[Tuttles Revenge]

then use whatever you need at the stack you are tying into but use 2”. Run it for a foot or more then have the pressurized line run into the larger two inch before it hits the y. Once the discharge leaves the 3/4 or 1” pressurized line into a 2” line it becomes a gravity drain. I would still use sch 40 as far as I could though.

edit: this is how I ran mine. The wet venting of the line probably is a no go by most plumbers but I didn’t have any other way to do it. Works great so far.

That installation is so far from code.. but I will admit that I did that same setup once for a bar sink.. I was probably in high school then.

 

[Shawnv92]

Thanks for the advice, Tuttles and JoeJee. I decided to go above the junction box / conduit, since it didn't seem right to squeeze the pipe between the conduit and drywall, and the Saniflo rep got back to me saying the Sanicompact discharges at 10-15 psi, and a vertical lift should be used if some pressure drop is desired.

I have completed a rough in of the drain (nothing is glued yet), and would appreciate a critique before I go with it (this is my first major plumbing project)

On the right is the Sanicompact waste line. A short horizontal stub with a ball valve connects to the saniflo, before turning up (through two 45 elbows) and then turning left (again through two 45 elbows). This is mated with a 1" to 1.5" reducer, which is then tied to a s 1.5" sweep tee, which goes to the vertical drain. On the left is the pipe for the sink drain. There was a stud getting in the way above, hence the sink horizontal run is at a lower level than typical sink height. A sweep tee and fixture tee combo is used to bring the p-trap opening at the right height, and also to connect a AAV (not connected yet) for sink venting. I have also left a stub of pipe capped on the left, in case we decide to remodel the closet on the other side of the left wall into a shower stall with the Sanishower pump.

 

[Tuttles Revenge]

You will need a transition glue to get PVC to weld into ABS. or use a rubber connector like you have on the vent/vertical pipe.

 

[Shawnv92]

You will need a transition glue to get PVC to weld into ABS. or use a rubber connector like you have on the vent/vertical pipe.

Yes, the white PVC 1.5" coupling to 1.5" ABS sleeve connection has been made using transition (green) cement. Everything else on PVC side uses PVC primer and cement, on ABS side ABS cement.

 

[Cam Duncan]

shawnv92 - I'm about to do a very similar project. How did it go?

Also, in the instruction manual it says to tie into a minimum 3in stack. Did you ask Saniflo about this? Seems a bit excessive if the DFU's support less... I also want to tie into a 2" stack (2" vent, 3" further down the stack).

Thanks,

Cam

 

[Jeff H Young]

if the instruction read a 3 inch stack is required then thats whats required. you might call if you have a question if the wording isnt clear . but plumbing code requires to follow code or manufacture instructions whichever is strictor .