I decided to check a popular 2500 GPH pump for above ground pools, to see what the actual flow rate was and used a separate tank so I could actually measure flow correctly.
Installed a pressure gage into the lid of the canister and measured flow at startup pressure of 0. I got 20 GPM or 1200 GPH and at 2 psi, got 720 GPH or 12 GPM. Actual max pressure output was 5 PSI.
Removed pump end to check the design and found the impeller to be much smaller than the pump housing (volute). The smaller impeller allows it to slip through water (not pumping). The slippage becomes worse as dirt builds up on the cartridge.
' The inlet hose size is 1 1/2" diameter which is adequate, however, the transfer pipe from the pump to the canister (inside the pump enclosure) is only 1" diameter. The small size pipe increases friction loss and drops flow rate considerably.
The return hose is 1 1/2" which is adequate for its length.
It does not take much, to plug a cartridge, at 5 PSI. and cleaning the cartridge does not remove all the small particles lodged in the pleat fabric. Consequently, cartridge life is short and needs to be thrown away.
Installed a pressure gage into the lid of the canister and measured flow at startup pressure of 0. I got 20 GPM or 1200 GPH and at 2 psi, got 720 GPH or 12 GPM. Actual max pressure output was 5 PSI.
Removed pump end to check the design and found the impeller to be much smaller than the pump housing (volute). The smaller impeller allows it to slip through water (not pumping). The slippage becomes worse as dirt builds up on the cartridge.
' The inlet hose size is 1 1/2" diameter which is adequate, however, the transfer pipe from the pump to the canister (inside the pump enclosure) is only 1" diameter. The small size pipe increases friction loss and drops flow rate considerably.
The return hose is 1 1/2" which is adequate for its length.
It does not take much, to plug a cartridge, at 5 PSI. and cleaning the cartridge does not remove all the small particles lodged in the pleat fabric. Consequently, cartridge life is short and needs to be thrown away.
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