Flow Rate - 47 GPM -Can I Increase the rate

[richmgreen]

Hi. I have a meter located about 4ft from the filter and just before the heater. All my lines above and under ground are 1 1/2" pvc. I have 1 suction line. It's the line from the skimmer to the pump. About 15ft. The line comes out of the ground by about a foot and then is connected to the pump with a horizontal connection distance of maybe 7". Doesn't seem like much opportunity to increase my flow rate. Is it mostly effected by the suction side only? On the pressure side, it comes out of the heater and then into the salt gen and then to the return valves. I'm looking to install a variable speed pump this spring. Was just looking to maximize my starting point.

Looking for any ideas on increasing flow rate if possible. Obviously, replacing the underground lines with 2" is not possible at this point.

Thanks
Rich

 

[JamesW]

Looking for any ideas on increasing flow rate if possible.

Why?

 

[ajw22]

47 GPM is good enough for your heater.

Why do you think you need more flow?

Many of us run our VS pumps at the minimum speed’s necessary for our SWG or heater or other equipment.

 

[richmgreen]

I’m thinking that to make the electrical savings pay for the high cost VS pump, I’ll need to cut the speed (rpm) in half. 1/2 of 47 gpm is pretty low. Trying to get years of payback in a reasonable time frame.

 

[ajw22]

When you cut the RPM in half you reduce electric draw by 75%.

What is the minimum flow your HP requires?

 

[JamesW]

1/2 of 47 gpm is pretty low.

Not really.

You only need enough flow to make the skimmers, SWG and/or heater work.

Skimmers need about 10 to 15 gpm each.

SWGs need about 15 to 20 gpm.

Heaters needs about 25 to 40 gpm.

 

[richmgreen]

When you cut the RPM in half you reduce electric draw by 75%.

What is the minimum flow your HP requires?

Shows 30 min but optimal is 45-50gpm. We don’t run the heater 24/7. Just beginning of season and on Fridays .. again, early in season to swim on weekend.

 

[Jimrahbe]

Rich,

You are just over thinking this..

Just get the VS pump and run it at whatever speed works for what you are trying to do.

You really don't even need to know the flow rate to successfully maintain a pool.

Thanks,

Jim R.

 

[Darin]

47 gpm? why so high. If i was you i would be decreasing to save a lot of money.

Just do what Jimrahbe says above, and also remove that flowmeter. It is not needed.

 

[ajw22]

Shows 30 min but optimal is 45-50gpm. We don’t run the heater 24/7. Just beginning of season and on Fridays .. again, early in season to swim on weekend.

You will find there is no visible difference in your heater operation with flow in the low 30s versus high 40s. But there will be a visible difference in the pump energy usage.

To get full benefit from the VS you need automation that will ramp the speed up when your heater turns on and stops the pump down when your heater is off. Automation lets you always have your pump at the most efficient speed.

 

[1poolman1]

Hi. I have a meter located about 4ft from the filter and just before the heater. All my lines above and under ground are 1 1/2" pvc. I have 1 suction line. It's the line from the skimmer to the pump. About 15ft. The line comes out of the ground by about a foot and then is connected to the pump with a horizontal connection distance of maybe 7". Doesn't seem like much opportunity to increase my flow rate. Is it mostly effected by the suction side only? On the pressure side, it comes out of the heater and then into the salt gen and then to the return valves. I'm looking to install a variable speed pump this spring. Was just looking to maximize my starting point.

Looking for any ideas on increasing flow rate if possible. Obviously, replacing the underground lines with 2" is not possible at this point.

Thanks
Rich


View attachment 472643

For pool purposes, the water speed in 1.5" PVC should not exceed 7 feet per second. That is right about what you have now at 47-48gpm.