I have a Hayward 1.5 hp pump with a flow rate of 70 gpm and a doheny sand filter with a flow rate of 50 gpm. I’ve read a bunch of people say the flow rate of the filter should exceed the pump, so I looked into my filter to see which pump they sell with it and found out that it’s the same Hayward pump I have, just with the doheny label on it. So what is the truth about matching pump to filter?
What should the sand filter gpm be for a 70 gpm pump?
- Thread starter greenpoolboy
- Start date
The pump should not push more water through the filter than its designed to handle. But most people do not run the pump at its max flow rate. You save electricity and the filter works better at lower pressure (assuming the pump is variable speed and the speed can be turned down). So we tend to recommend using RPM instead of GPM.
15 gpm/sqft. for backwash.
For a 3.14 sqft surface area, you want 47 gpm on backwash, not more or less.
For filtering, you want a maximum of 15 gpm/sqft.
So, 47 gpm or less.
For a 3.14 sqft surface area, you want 47 gpm on backwash, not more or less.
For filtering, you want a maximum of 15 gpm/sqft.
So, 47 gpm or less.
When plumbed to a filter system that pump doesn't move 70 GPM. That rating is on an open line with very little head, not pulling and pushing water through corrugated 1.5" pool hoses,
