Need help with 2 pumps on one return line.

[Biglurr54]

I need some help with my return pump plumbing. I had two separate 20amp GFCI circuits run to my basement sump. I plugged an EB832 into each circuit. Im al looking to get redundancy and efficiency with my pumps.

I only have one return line to the sump and it’s a 1.25 pipe. I teed off the return pipe and added a check valve on both lines coming from the pump. The order from the sump up goes: Sump, Pump, check valve, tee (combining two pumps to one pipe), then up to the tank.

I was running 1 sp6 pump which had a lot of flow. I changed that out for two sp4’s. according to my math, the two sp4’s should have produced more flow than the single sp6. Well that was not the case. It produces less flow and consumes more energy. This is the opposite of what I am looking for. How should I move forward?

• Replace one sp4 with the sp6 and write apex code to turn the sp4 on if the sp6 stops drawing power or falls out of range.
• Go back to 1 sp6 and not have the back up pump
• Run the sp4s in series instead of parallel.

Running an additional return line is not possible at the moment.

Does anyone hav any information on two pumps feeding the same line? Do they fight each other or reduce flow due to 2 of them on one line with check valves? If I add a larger pump and a smaller pump, will the larger pump push against the flow of the smaller pump and reduce its flow?

 

[Biglurr54]

I need some help with my return pump plumbing. I had two separate 20amp GFCI circuits run to my basement sump. I plugged an EB832 into each circuit. Im al looking to get redundancy and efficiency with my pumps.

I only have one return line to the sump and it’s a 1.25 pipe. I teed off the return pipe and added a check valve on both lines coming from the pump. The order from the sump up goes: Sump, Pump, check valve, tee (combining two pumps to one pipe), then up to the tank.

I was running 1 sp6 pump which had a lot of flow. I changed that out for two sp4’s. according to my math, the two sp4’s should have produced more flow than the single sp6. Well that was not the case. It produces less flow and consumes more energy. This is the opposite of what I am looking for. How should I move forward?

• Replace one sp4 with the sp6 and write apex code to turn the sp4 on if the sp6 stops drawing power or falls out of range.
• Go back to 1 sp6 and not have the back up pump
• Run the sp4s in series instead of parallel.

Running an additional return line is not possible at the moment.

Does anyone hav any information on two pumps feeding the same line? Do they fight each other or reduce flow due to 2 of them on one line with check valves? If I add a larger pump and a smaller pump, will the larger pump push against the flow of the smaller pump and reduce its flow?

 

[Biglurr54]

I want to note that I know two dedicated lines would be best. When I upgrade the tank, i will run two dedicated 1.25 lines for the returns. Thats not happening right now.

I also want to note that I am not relying on the check valves for anything other than preventing one pump pushing water through the other pump. The sump is sized to handle all the water in the event of a power failure with out the check valves.

 

[Billdogg]

I would go with the one larger pump and just put a gate valve on it to temper the flow as needed.

 

[JoshH]

I agree, going back with your 1 SP6 and if you wish use the 4 as a backup or sell the 2 4s and get a second 6 would be your best course of action. The issue with stepping down a size in pumps is the smaller pumps can't handle the same head height. Regardless of whether or not there are two they both have the same height restrictions compared to the SP6

 

[Biglurr54]

I agree, going back with your 1 SP6 and if you wish use the 4 as a backup or sell the 2 4s and get a second 6 would be your best course of action. The issue with stepping down a size in pumps is the smaller pumps can't handle the same head height. Regardless of whether or not there are two they both have the same height restrictions compared to the SP6

I actually have 2x SP6's for the future upgrade. Im considering going with Jebao dcp 15000. They seem to have better head pressures and more flow at lower wattage according to their flow charts. I have one ordered. I will put on against the Sp6 in my system and see which moves more water.

Between 2x sp4s 2x sp6s and 2x dcp 15000 something should fit the bill and work. It will be interesting to see how it all works out.

My plan is to tune the overflow to have the full siphon balanced perfectly. Then i will swap pumps and see if the overflow is still balanced. This should give me an idea of which combo gives better flow.

Stay tuned

 

[Biglurr54]

Ok. 1 sp4 was replaced with the sp6. I turned off the remaining sp4 and I have more flow with just the sp6. I turned both on and got no difference in flow. So to recap. 1 large pump is better than 2 smaller ones on the same line. This makes me wonder about running in series. Maybe that is the answer to running two pumps on one line.

The dcp15000a come in Thursday. We'll see how they compare.