Dual return pumps on single return

splix · 05/09/2016, 03:23 PM

Is it possible to Y adapter two return pumps on a single return line going to the DT for redundancy purposes?
I know you cant have them going to a parallel T type fitting, they would need to be on a Y style fitting so flow is directed up and doesnt go from one pump into the other.
I'm just curious if it's possible or if it'll still cause back pressure issues with each pump.

Greybeard · 05/09/2016, 03:29 PM

As long as both pumps are pulling from the same compartment in the sump, and running to the same display tank, I see no reason why not. Mechanically, it's no different from simply putting on a bigger pump. If the overflows can handle it, no problem.

You're going to need back flow valves, to keep the working pump from pumping back to the non-working pump. Even with a 'Y', it's going to follow the path of least resistance, which is going to be the non-working pump.

Honestly, if I were going to do this, I wouldn't join them at all. 2 return pumps, both going directly to the display, independently. No reason to 'Y' them, unless you don't want to inlets, I guess.

Mr. Brooks · 05/09/2016, 03:39 PM

The only way a Y would work is with check valves. I wouldn't do this personally.

If you can't run two separate return lines for each pump, you can run them in series. One pump would pump directly into second pump. This would work.

splix · 05/09/2016, 05:37 PM

I was going to have them both running simultaneously.
It's a bit past the time to have dual returns. The tank has been running for awhile and is already drilled for a single return. Not to mention the sump is in the basement. I have an extra hole drilled between floors but still...

Are having pumps in series really a thing? I didnt think of that but if the upstream pump fails, will the downstream one really be able to push water through it?

05/09/2016, 03:23 PM	#1
splix Registered Member Join Date: Oct 2015 Location: Indiana Posts: 374	Dual return pumps on single return Is it possible to Y adapter two return pumps on a single return line going to the DT for redundancy purposes? I know you cant have them going to a parallel T type fitting, they would need to be on a Y style fitting so flow is directed up and doesnt go from one pump into the other. I'm just curious if it's possible or if it'll still cause back pressure issues with each pump.

05/09/2016, 03:29 PM	#2
Greybeard Registered Member Join Date: Jun 2015 Location: Buffalo, MO Posts: 651	As long as both pumps are pulling from the same compartment in the sump, and running to the same display tank, I see no reason why not. Mechanically, it's no different from simply putting on a bigger pump. If the overflows can handle it, no problem. You're going to need back flow valves, to keep the working pump from pumping back to the non-working pump. Even with a 'Y', it's going to follow the path of least resistance, which is going to be the non-working pump. Honestly, if I were going to do this, I wouldn't join them at all. 2 return pumps, both going directly to the display, independently. No reason to 'Y' them, unless you don't want to inlets, I guess.

05/09/2016, 03:39 PM	#3
Mr. Brooks MASVC Member Join Date: Apr 2007 Location: Simi Valley, CA Posts: 3,477	The only way a Y would work is with check valves. I wouldn't do this personally. If you can't run two separate return lines for each pump, you can run them in series. One pump would pump directly into second pump. This would work.

05/09/2016, 05:37 PM	#4
splix Registered Member Join Date: Oct 2015 Location: Indiana Posts: 374	I was going to have them both running simultaneously. It's a bit past the time to have dual returns. The tank has been running for awhile and is already drilled for a single return. Not to mention the sump is in the basement. I have an extra hole drilled between floors but still... Are having pumps in series really a thing? I didnt think of that but if the upstream pump fails, will the downstream one really be able to push water through it?