Reduce pool pump run time from 8hrs to 4hrs

[Cetanorak]

Hey all, inherited pool with new home. Intermatic timer was set by previous owner to run pump (Hayward TriStar SPX3200A with Century Centurion Motor B2840V1, 2.5 hp, 3450 RPM) 9a-5p daily. We live in Texas hill country, pool is 20-25K gallons no spa and no pool cover. I was planning to reduce the pump run time to 4 hours daily, set to run 9a-11a and 2p-4p. Any reason why this reduction in pump time would or could be a problem, assuming that I'm keeping up with proper chlorine levels and adequate surface skimming (by the skimmers...not me!).

My plan is eventually upgrade to a VS speed pump.

 

[Jimrahbe]

C,

As long as you keep your FC and CYA in the proper relationship you should be fine.

Not sure you will get a lot of skimming in 4 hours but that is just a visual issue.

Thanks,

Jim R.

 

[1poolman1]

Hey all, inherited pool with new home. Intermatic timer was set by previous owner to run pump (Hayward TriStar SPX3200A with Century Centurion Motor B2840V1, 2.5 hp, 3450 RPM) 9a-5p daily. We live in Texas hill country, pool is 20-25K gallons no spa and no pool cover. I was planning to reduce the pump run time to 4 hours daily, set to run 9a-11a and 2p-4p. Any reason why this reduction in pump time would or could be a problem, assuming that I'm keeping up with proper chlorine levels and adequate surface skimming (by the skimmers...not me!).

My plan is eventually upgrade to a VS speed pump.

You can always give it a try, but it may be better if you just ran it 9A-3P.

 

[TXpoolDIYguy]

Generally speaking you only need to run your pump long enough to cycle the water at least once per day, so we can do some quick math to see what that works out to. Cut the time down to that then make sure your chlorinator is keeping up.

So SPX3200A is actually the part number referring to the pump housing for the Tristar series, which is universal for all motor/impeller size combinations of that Series. The motor you specified is a 2.5HP with a 1.04 SF (2.6THP), which corresponds to the SP3220X25 model (see attached spec sheet). Unless your hydraulic head is >75ft (very high), or you have 2.5" piping, that pump is going to be pushing the max amount of flow that a 2" pipe can handle (~83GPM). At 83GPM you only need to run the pump 5 hours to turn the water once (assuming 25k gal pool).

If you want to get serious about energy savings, look into a VGreen VS replacement motor. It will mate up perfectly with the Tristar square flange. You would need the ECM27SQU (2.7THP) which may be hard to find since it's discontinued. The EVO is the new Century VGreen model, but it looks like they max out at 2.25THP, so you would have to downsize the impeller to the SPX3215C. Still should be more than enough to turn over your pool water.

*

Explore our Pool Pump Motors with 2.70 HP, 1 Phase, 60 Hz, 230V. Operating at 3600 RPM, this 48Y motor comes Totally Enclosed Fan Cooled, delivering reliable performance for your applications.

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www.regalrexnord.com

 

[mknauss]

Generally speaking you only need to run your pump long enough to cycle the water at least once per day,

Turnover is a myth.

Turnover of Pool Water - Further Reading

www.troublefreepool.com

 

[1poolman1]

Generally speaking you only need to run your pump long enough to cycle the water at least once per day, so we can do some quick math to see what that works out to. Cut the time down to that then make sure your chlorinator is keeping up.

So SPX3200A is actually the part number referring to the pump housing for the Tristar series, which is universal for all motor/impeller size combinations of that Series. The motor you specified is a 2.5HP with a 1.04 SF (2.6THP), which corresponds to the SP3220X25 model (see attached spec sheet). Unless your hydraulic head is >75ft (very high), or you have 2.5" piping, that pump is going to be pushing the max amount of flow that a 2" pipe can handle (~83GPM). At 83GPM you only need to run the pump 5 hours to turn the water once (assuming 25k gal pool).

If you want to get serious about energy savings, look into a VGreen VS replacement motor. It will mate up perfectly with the Tristar square flange. You would need the ECM27SQU (2.7THP) which may be hard to find since it's discontinued. The EVO is the new Century VGreen model, but it looks like they max out at 2.25THP, so you would have to downsize the impeller to the SPX3215C. Still should be more than enough to turn over your pool water.

*

Explore our Pool Pump Motors with 2.70 HP, 1 Phase, 60 Hz, 230V. Operating at 3600 RPM, this 48Y motor comes Totally Enclosed Fan Cooled, delivering reliable performance for your applications.

www.regalrexnord.com

*

www.regalrexnord.com

Nidec Neptune NPTQ270 is a great way to turn that pump into a VSP.

 

[TXpoolDIYguy]

Nidec Neptune NPTQ270 is a great way to turn that pump into a VSP.

Does it have automation support?

 

[1poolman1]

Does it have automation support?

It will work with a Waterway Oasis, I've done that as Waterway uses the motor on their VSP.

It is able to use relay inputs and has this in the manual:
RS-485 Port
The RS-485 port allows you to connect an external controller. When connected, the UI no longer
controls the motor. Commands from the external controller take priority. Other than enabling or disabling
Remote Control and possibly the Node ID, the UI plays no role in communication. Contact US
Motors/Nidec Motor Corporation for the proper communication protocol. If an external controller is used,
make sure the line is an isolated, non-grounded connection.

 

[TXpoolDIYguy]

Turnover is a myth.

Turnover of Pool Water - Further Reading

www.troublefreepool.com

Hence why I said "generally speaking" and "then make sure your chlorinator is keeping up".

"Run your pump long enough to keep chlorine, skim the pool, and mix chemicals" is not exactly a good set of instructions for someone who is trying to find a starting place for how long to run their pump. The turnover is just a simple rule of thumb for starting guidance. Then you tweak from there as needed.

 

[Jimrahbe]

The turnover is just a simple rule of thumb for starting guidance. Then you tweak from there as needed.

TX,

I have three saltwater pools and have never calculated my turn overs... I don't even know how to spell GPM, and all my pools work just fine.

Many people come here all concerned about what speed they need to run to make sure they "turnover' their pools X times day.

If you use the TFP pool care process, calculating turnovers are just not necessary. Unfortunately, most myths are very hard to not believe in when you don't really understand how things work.

We feel it is a disservice to our members to perpetuate the turnover myth.

Thanks,

Jim R.

 

[reggiehammond]

My plan is eventually upgrade to a VS speed pump.

Now is a great time to upgrade to a VSP. You can accomplish the same results using ~200 watts as you currently do using ~2500 watts. Given that we don't close Texas pools, those electrical savings add up and you'll see payback in a shockingly short amount of time.

$.03 per hour versus $.35 per hour, with $.15/kWh electrical rate.

A VSP allows you to just run 24/7 to keep the pool constantly skimming, filtering, and creating chlorine via a SWCG.

 

[TXpoolDIYguy]

I understand what you are saying, but if someone plans to turn over their water once per day and is able to properly maintain FC, I don't understand how that is them being disserviced. In almost every case it will result in electricity savings by running an oversized pump fewer hours.

If someone had told me that when I first bought my house with my pool I would have saved thousands of dollars in electricity cost by now.

 

[mas985]

I understand what you are saying, but if someone plans to turn over their water once per day and is able to properly maintain FC, I don't understand how that is them being disserviced. In almost every case it will result in electricity savings by running an oversized pump fewer hours.

Because the pool may only "need" 0.1 turnovers. So it is being run 10x longer than it needs to.

 

[Jimrahbe]

TX,

I think we might be saying the same thing, just not the same way...

We do not care if a pool owner wants to turnover his water a 100 time a day or .1 times a day... Whatever works for them works for us..

The myth that we are taking about is that X turnovers a day are 'required' to keep your pool algae free. That is just not true.

We are just trying to tell pool owners that they don't have to worry about turnovers, one way or the other.

Thanks,

Jim R.

 

[Newdude]

Just like FC demand / daily UV loss, the amount of skimming/filtering a pool needs varies greatly throughout the season. At the same pool. Forget about blanket statementing all pools all the time.

It will need considerably more skimming and filtering in the spring/fall and much less in the peak season.

The chemicals take 15 to 30 minutes a day to mix regardless of how much debris is falling into the pool. That part is constant at least.