Using a pump to relocate a slop sink Drain.

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Art

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Hello Everyone,

First just want to thank you for taking the time to read my post. I would like to relocate my sink and washer to the other side of the room in order to create easier access to the exit door. The laundry room is located in the garage which is on slab. I am trying to avoid tearing up my garage floor to put in a drain so i figured i use a basement toilet pump so I can reroute the drain to go 8 feet up across the ceiling and then down to the original drain. Has anyone done this before or is this bad Idea. I attached a model of the original layout and what i am looking to do. Hopefully the pictures help explain what i am trying to do.

Link to an example pump
https://www.saniflodepot.com/produc...MI7_GQpLGo4wIVCbbICh0fbgpuEAkYAiABEgKYH_D_BwE
 

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shopping
What you are showing for a pump is overkill for gray water only.
 
I assumed that it was. I just used that as an example. So is doing something like that feasible or do you see any issues with the idea?
 
look up liberty laundry pumps they come in 1/1/2 and 2 inch....the 2 inch will grind small stuff the 1 1/2 will not use a pvc (quiet ) check valve with a valve and union above it for easy and no mess swap out
 
I assumed that it was. I just used that as an example. So is doing something like that feasible or do you see any issues with the idea?
No issues, it's done quite a bit by me. Lots of radiant heat and we dont cut concrete with heat lines in it.lol
 
Hey everyone so this is the game plan. I plan to use pex pipe for this project. I am going to connect the 1/2 pex to a 1/2 copper feed line for the hot and cold water using 1/2 in Brass PEX Barb x 1/2. Female copper Sweat adapter. Then route the lines to the other side and split them with a Brass barbed Tee for the hot and cold water in order to connect the sink and washing machine. For the draining of the new slop sink location I was going to use 404 or 405 Liberty pump thanks to Geofd recommendation. Plum waste line 8 feet up and 10 feet across back down to the original waste drain. I attached a diagram just incase none of this makes sense lol. What you guys think.
 

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Just looking at the pumps discharge rate(GPM), which for the 404 Liberty pump, would be around 40 GPM at the total discharge head once the flow fills the pipe. In other words the total discharge head would be the elevation difference between the pumps water level and the point of free flow discharge.
How are you tying the discharge into your drainage system? Since once you enter a gravity system the pipe must be capable of flowing 40 gpm. The consequences could be water backing up into a fixture drain. On the other hand, that flow rate would be intermittent since the pumps only holds 4.3 gallons and would likely cycle on and off depending on the rate of inflow from the sink/washing machine.

Without trying to calculate the flow rate from the sink to the pump and the off time of the pump, I would say you don't need to make that pump discharge pipe 2" as shown. As that would only increase the flow rate slightly. A 1-1/2" would help slow it down a little bit. Then if there is a case of backing up into a fixture due to the excessive flow rate, you could throttle down the flow from the pump with that discharge valve. That's not a problem with centrifugal pumps and typically would reduce the HP demand slightly.

Just so you understand how it works, the 8 foot lift (or a portion of it) is cancelled out by the drop at the other end. So then all you have is friction loss based on flow rate. With 1-1/2" pipe, friction loss will increase and help educe the flow a bit. So as the curve shows, the pump starts off at around 30 GPM and once the pipe fills up quickly climbs to about 40 GPM. It takes a 4" gravity line to handle that kind of flow. But like I said it may be on and off based on the pump cycling.

Just a heads up.


Liberty 404 pump.jpg
 
You are going to have to discharge your washer into the laundry sink so the pump can keep up.
 
Thanks for your input Everyone. Diehard i didn't even think of that. Should I look into a pump that has less power? Only reason I chose a stronger pump was to make sure it will clear the 8 foot high pipe. As for controlling the flow rate I was going to install a discharge valve as you mention in order to control the pump from pumping to fast. Should i add a discharge valve on the gravity pipe (i.e. the 8 foot decent pipe) to limit flow just incase its to much? it also looks like the drain pipe that i would be connecting looks to be 2 in to 2 1/2 inches. SHEPLMBR thank you for the heads up. I was planning on having the washing machine discharge into the sink to be safe just incase the pump ever dies i'm not stuck with a messy puddle.
 
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It wouldn't matter where in that pump discharge line you put that valve. On the 8' rise, on the horizontal, or on he drop. It's all part of that force main until it sees a free fall/gravity condition.
It's not going to see that in a 2 or 2-1/2 gravity pipe. The 2 or 2-1/2" would likely become pressurized and try to take the path of least resistance, like a connected fixture for example.

We just had a case, here in the forum, where a fellow had a similar situation. He was trying to find out why he was getting a small geyser out of his sink when his sump pump came on. Come to find out, the sump pump discharge line was connected to a relatively small drain line from the sink.

The flow capacity of a sloping drain line varies based on slope, roughness of the inner surface, and source of information.
A 2" fairly smooth line, at a min. slope of 1/4"/foot, is listed as 8.43 to 11.5 gpm(depending on source) for half full pipe. (Half full because that's what it is typically designed for.) So for a 2" pipe you could estimate approx. say 9 gpm x 2(for full pipe) = about 18 gpm. A 2-1/2" pipe may get up to about 30 gpm or so.
So you would definitely have to throttle that flow down a bit to avoid it backing up into anything.
 
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I am confused did i misunderstand something?
 
I changed my previous post to oops when I saw your response. Then I edited it to respond your post #9.
So update the page and look back at my post #10
 
Continuation of my post #10...

If you look back at that curve for the pump, you would have to dissipate(create a head loss with a valve) roughly 16 feet of head to get the flow down to about 18 gpm.
 
That's not a problem with a centrifugal pump, to have it running at a higher head and lower flow. It actually uses less HP.

Although you could look at a smaller pump system.
 
Okay thanks Diehard. I am new to this so I really appreciate all your help and patience. So picking a centrifugal pump or a smaller pump with less GPM will solve my issue? I am open to use any pumps that would make sense to use. Also I probably will cut the wall where the current drain goes into to see if it connects to a larger pipe that can handle the higher water flow. Finally if the pump ends up to be feeding into a 2 in drain and i use the current talked about pump would using 1 1/2 pipe and adjusting the discharge valve until it reaches enough resistance to create 18gm flow work? In the end it looks like it would make sense to get a pump that does 15 to 20 gallons a minute to solve the issue.
 
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Okay thanks Diehard. I am new to this so I really appreciate all your help and patience. So would picking a centrifugal pump solve my issue or a pump that pushed less GPM ? Yes, but you have to be careful as to how they advertise their head and flow performance ratings. A curve is the best way to view its capabilities. Keeping in mind, as previous touched upon, if you pump up 8 feet and then drop 8 feet the only head loss is the friction caused by the flowing water at a particular velocity. I am open to use any pumps that would make sense to use. Also I probably will cut the wall where the current drain goes into to see if it connects to a larger pipe that can handle the higher water flow. That would be a good idea. Finally if the pump ends up to be feeding in to a 2 in drain and i use the current talked about pump would using 1 1/2 pipe and adjusting the discharge valve until it reaches enough resistance to create 18gm flow work?
There is no reason to make that line a 2", as it's not handling sewage. The 1-1/2" makes a very small difference but would help a little to reduce the flow rate. The valve, of course, can be throttled down to whatever it takes to prevent excess pressure/flow to back up into any nearby sink. But ideally, tying into a larger gravity line would be the preferred way.
I haven't looked at any pump systems but I feel they are becoming more popular for use under a service sink. I've been retired for a while now. So many of the products are a learning experience for me.
 
Okay thank you. So this weekend I will cut into the wall to see what size pipe the current drains into. Will also research pumps with lower GPM. Once again thank you for all your help.
 
Okay thank you. So this weekend I will cut into the wall to see what size pipe the current drains into. Will also research pumps with lower GPM. Once again thank you for all your help.
Okay ! Good luck.
I just spent a few minutes looking at a few pumps. I noticed one that doesn't use a sump but rather the pump suction gets connected directly to the sink drain. Being a bit curious as to recycle frequency, ETC., I called them(Myers Pumps). Without getting into the details, it turns on and off based on the presence of a specific amount of water sensed and requires the owner to adjust the discharge rate(with a valve in the discharge line) for proper functioning. I WOULD NOT RECOMMEND THIS TYPE FOR YOU.

I haven't gone too far in my search but they don't seem to get much smaller. I would suspect, however, that a solids handling pump MAY BE less, as they typically have a less efficient impellar, to allow solids to pass.

Happy hunting.
 

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