Verifying correct pump size

[harleythedog]

Hello

Looking for some verification on the correct pump size for my pool. In ground 15,000 gallon, 1.5in pipe, 2 returns, 1 skimmer, no water features, no spa. Currently use an automatic pool cleaner (baracuda) connected to the skimmer and have solar heat panel on 1st floor roof about 8ft up. My current pump is a 3/4hp Jacuzzi High Head and I would like to replace it for a few reasons. Based on the reading/research I believe I would be ok with a 3/4HP Hayworth Super Pump or a Super II Pump (or Pentair Superflo). However when I reached out to a couple of pump resellers, one suggested a 1.5HP Whisperflo while the other one suggested a 1HP Super Pump and advised against the Super II. I am not sure but it seems that a 1.5hp Whisperflo is a bit much and even a 1HP Superpump the same. If I am not mistaken at 40gpm a 3/4HP would turn the water over in ~6 hours. Am I off here and I am better off with a 1HP ? Superpump ? Super II ? I am leaning towards Hayward simply because there are several local distributors but honestly not set on it. Appreciate any guidance.

I am also replacing the existing 50cu ft cartridge filter with a 120-150 cu ft filter. A secondary question is the 150cu ft filter has 2" ports and my pipe is 1.5", any issues with reducing this to 1.5" ?

thanks !
fs

 

[jblizzle]

Welcome to TFP!!!

First you have to realize that the HP does not tell the whole story. The Hayward Super II and Pentair Whisperflo pumps are much larger pumps than the Hayward Super Pump and Pentair Superflo.

My pool is slightly larger and I have solar as well. Runs fine with the smaller Pentair Superflo ... or you could get the Hayward Super Pump 1HP with is basically the same thing. The smaller the pump, the lower the electrical cost to run it. I would certainly recommend upgrading to a 2-speed version though to save money when you do not need the solar running.

FYI, for you size pool and location, I would recommend a filter at least 200 sqft, and bigger is better. No problem using reducers to change from 1.5" to 2" when needed.

 

[JasonLion]

Your best bet is one of the smaller two speed 1 HP pumps, like the Hayward Super Pump or Pentair SuperFlo.

A larger pump isn't better, it just uses more electricity to do the same job. Circulation and filtering really don't need much power. A two speed pump can be run on low speed almost all the time, saving a significant amount of electricity over high speed. With a two speed you have high speed for the few things, like manual vacuuming, that needs high speed, and low speed for all the rest of the time to save money.

 

[harleythedog]

Thanks, a smaller pump was my thought as well. I just found it strange someone would recommend a 1.5HP whisperflow, seemed a bit much. At one point they also suggested a 2HP version.

Out of curiosity, why not a 3/4 HP which is what I have now vs the 1HP ?

For a 2 speed pump, when the pump is on low speed, would the solar diverter need to be off or would the pump have enough pressure to cycle the water through the solar panels 8 ft up ? The current solar is auto valve temp controlled.

again, thanks for the feedback.

 

[jblizzle]

The 3/4HP 2 speed are usually hard to find and often cost more than the 1HP. Plus they can be a little too small to run solar.

You will want to run the pump on high when you are utilizing the solar heating. It heats better and low is usually not strong enough.

 

[Hayward Pool]

It is always nice to see great advice from all the contributors.