Advisability of retrofitting to a two speed pump

[mas985]

Sentient,

A two speed pump will nearly always save you money assuming you run the pump on low speed most of the time. If you go with the same HP pump but in two speeds, the lower speed will have about half the flow as high speed so the turnover is twice as long. This means you will have to run it twice as long on low speed than high speed for the same filtration. The power usage at low speed for some pumps is about 30% of high speed (60% reduction). But since your running the pump twice as long, you will save close to 30% of the power than high speed.

Even without the rebate, the savings would pay for the pump in about a year.

[Sentient]

Sentient,

A two speed pump will nearly always save you money assuming you run the pump on low speed most of the time. If you go with the same HP pump but in two speeds, the lower speed will have about half the flow as high speed so the turnover is twice as long. This means you will have to run it twice as long on low speed than high speed for the same filtration. The power usage at low speed for some pumps is about 30% of high speed (60% reduction). But since your running the pump twice as long, you will save close to 30% of the power than high speed.

Thank you, that helps a bunch. So now I just need to pick a pump. There is a two speed version of the pump I have now, so I presume plumbing it in should be relatively straightforward, the dimensions should be identical. I think I will go ahead and do it.

I thank you all for the quick feedback and great information.

Sentient

[cgc2]

How many gallons is your pool ?
A two speed pump will save you money. I have a 30k gallon in ground pool, running a Autopilot SWG (cell upsized for 60k gallon pool), and a Automatic Pool Cleaner (Dolphin).
I run a 1hp Pentair Whisperflow @ 4hrs high, 5 hrs low, and it keeps my water sparkling clean and with a Clorine level of 2.5-3.0 ppm.

BTW....I live on the other side of the Grapevine and work for the utility co. offering you that rebate.

[South_Texas_Sun]

We're just getting to the final stages of pool construction and we're going to be needing 3 pumps.

One for pool circulation, one for water features, and one for the spa.

I'm thinking that 2 speed pumps might be useful for the pool circulation, and spa (with some of the jets closed), but how about the water features?

We have 2 jandy two-foot sheer descents and a large grotto waterfall (2 inch pipe) that flows over the top of a cap rock and into the pool. Is a 2 horsepower pump an overkill for water features? I'd like to be able to let it run for the kids and I'm afraid that after I get our first pool-present electric bill, I'll be reluctant to let the kids play in it all the time when we don't have company or other special occasion.

You see, I'm somewhat of a .......(ahem)........cheapskate.

Thanks

[cgc2]

Well, "you gotta pay to play", and electricity production aint cheap anymore.
A 2 speed could work on the water feature , i.e., rock water fall, etc.
But to apply it to a shear decent...I dunno, I dont think your going to push enough volume of water when you drop to the lower rpm, so I would work with a high efficiency single speed if it were mine.

I have a 1.5 hp single speed on my 5 ft shear decent, and I control the volume of water on it with a valve.
I do notice on the electric bill when the wife and kids have been using it.

Pentair has a new Variable Frequency Drive pump that I think over time will have applications in water features. No doubt it will probably carry a hefty retail price.

[CarlD]

I have had a 2spd 1-hp Hayward SuperPump for 4 years now and will NEVER have a single-speed again.

I don't do anything fancy--there's a switch on the back of the motor for hi/lo speeds. That's enough for me.

My pool is almost 20,000 gallons and I run lo almost exclusively--even with solar panels. I have NO troubles with the skimmer this season, so if you do, check the line and any ball-valves for restricters. Last season I put in a new valve and it had a restricter so skimming wasn't good. Pulled out the restricter and it's FINE even with a skimmer sock.

High speed is if I really want to agitate the water, speed up the skimmer, backwashing and for the return side pool cleaner (the Dolphin is in the robot hospital..)

Definitely get a 2 speed. Get a higher quality pump and you'll probably be able to get one that uses elec more efficiently at hi AND lo.

[South_Texas_Sun]

Thanks for the reply fellows. The 2-speed pumps sound good and I guess I'll try to wheedle 3 of them out of my pool builder.

As part of our original pool contract, he "included" $3600.00 worth of Hayward Goldline (Aqualogic) pool controls. Then later, he informed me that the control unit we are getting only has 4 outputs. I checked Ebay for the going price of a 4 output unit and found it for around $500.00.

Either there's some horrifically expensive options for Aqualogic, or the PB owes me $$$ in electronics.

Thanks again.