Intelliflo gallons pumped per kwh

[del]

I am trying to figure out if about 900 to 1000 RPM is really the best RPM range for maximum efficiency in terms of gallons pumped per kwh of electricity for an Intelliflo pump. I tried to gather some data from my system and got about 35 GPM (calculated from XLS spreadsheet) for 800 RPM and 116 watts. I also got 128 watts for 450 RPM which does not seem to be accurate. The calculated value makes no sense from the xls table on an old post on this site. Anyway, does anyone have gallons pumped per kilowatt hour for flow rates in the range of 450 RPM to about 1200 RPM? This is really just for to satisfy my curiosity, so its not a big deal.. My pool is about 25000 gallons. Thanks.

Del

 

[mas985]

I have a spreadsheet in my signature that will give you that but I have already done that analysis and for most plumbing systems, the Gallons/watt-hr peak between 800 and 1100 RPM.

 

[chiefwej]

The answer to your question isn't an easy one and will vary depending on your plumbing, the position of your control valves and even how clean your filter is at the time. Most find that 1000 rpm is their most economical speed.

I have an Inteliflow 011018 and I find that I can run the pump at 1000 rpm using just over 100 watts. The actual flow will vary depending on which valves have open. Also there seems to be a slight increase in power required as flow resistance increases which would further complicate the calculations. I have a flow meter in my system, but almost never even look at it. I did consult it when initially setting up my speeds for the pool cleaner, solar system and the SWG, just to insure that my speed setting were sufficient to supply the flow necessary for each task. Like others my fall back speed is 1000 rpm, but I increase it as needed for functions other than just filtration.

The flow relationship to the power required (or even the rpm) is not a static number. Just consider rpm vs wattage, and let it go at that.

 

[JamesW]

"Also there seems to be a slight increase in power required as flow resistance increases"

Power usage typically decreases as flow resistance increases at the same rpm. This is because the flow decreases with increasing resistance.

Power increases as flow increases.

Google Intelliflo Flow and Power vs. Flow (all or images) for the pump curve that shows how power increases as flow increases.

For example, at 3450 rpm, at about 67 feet of head, the flow will be about 120 gpm and the power usage will be about 3,000 watts.

However, if you increase the resistance to about 92 feet of head, the flow will drop to about 40 gpm and the power will drop to about 2,000 watts.