Getting a better turn over rate

[mas985]

I would like to see how many gallons per minute (gpm) I can get out of my 2 HP pump (2 inch line) and 140 gpm rated filter. In normal operation I tend to max out at 80 gpm, however when I "backwash" or "rinse" I get about 120 gpm flowing though the plumbing. Not sure why normal operation lowers the gpm to 80.

This is normal and it is because there is a lot more head loss in normal operation than there is in backwash operation. When in backwash, the water no longer travels through the return pipe, fittings, eyeballs and heater which all add head loss.

But to see if 80 GPM is reasonable for your setup, I would need to know a lot more detail:

Suction pipe diameter (e.g. 1.5", 2", 2.5")
Average length of suction pipes
Number of individual suction pipes from the pool to the equipment
Number and type of suction side valves
Current Pump Make/Model
Height of pump relative to the water level
Pipe size between pump and filter (e.g. 1.5", 2", 2.5")
Filter type, size and multi-port valve size
Filter PSI reading at the desired valve settings and pump's highest speed setting
Height of pressure gauge relative to the pump center line
Heater - yes or no
Number and type of return side valves
Return pipe diameter (e.g. 1.5", 2", 2.5")
Average length of return pipes
Number of individual return pipes from the equipment to the pool
Number of return eyeballs (usually more than the number of pipes)
Return eyeball inner diameter (e.g. 1", 3/4", 1/2")

[Ecozadd]

Thank you Pool Doc & mas985,

I'm thinking that the 80-85 gpm I currently get is probably the best i can do. You are right that we have a mess of piping and products installed that is probably not going to cut it for a commercial industry pool for very long. It is now up to me to sort out a way of getting the pool re-plumbed and done by commercial pool pros this time around.

Great forum and i'll be back soon with more questions.