variable speed/flow pumps with saltwater chlorinators

[mgianzero]

I'm really interested in going green by trying a Pentair Intelliflo pump to replace my Jandy stealth pumps. I also have an Goldline saltwater cell I've used for years which I love.

Here are my two concerns:
1) I've been told my a local pool shop that these variable flow pumps at the very low flows used for high efficiency won't work with saltwater chlorinators. Is he right? Maybe I could get around this by running at higher speed/flow for an hour a day and then step down to low flows for the remainder of the pool circulation turnover each day?

2) Also, can you run a suction cleaner with these variable flow pumps or do they not work at these low flows as well? How do you get around this?

Marc

 

[JasonLion]

Welcome to TFP!

An IntelliFlo pump at it very slowest speed is not always quite enough for a SWG. However, all you need to do is to turn it up just a little and you should be fine. The speed will still be slow enough that you will save lots of electricity.

A suction side cleaner is more problematic. They usually need noticeably higher speeds, though hardly full speed. With a suction side cleaner you will probably want to run on a speed sufficient for the cleaner only a small part of each day, and turn down to a lower speed most of the time. Depending on how much you want to run the cleaner, this will have more of an impact on your electrical savings, though you should still save some.

 

[spishex]

A PMSM motor like you'd get on the Intelliflo is more efficient across it's entire range of speeds than an induction motor at the same speed. The ability to run the pump at very low speeds and then increase flow for backwashing, vacuuming, etc. allows for even more savings and is much more efficient than the low setting a two-speed motor, but it's not as if you have to run it at a minimum setting to see an improvement in efficiency.

Depends on your pool, but in every case I've seen the lowest flow rate that would provide sufficient flow to the skimmers was more than enough to operate a SWG.

 

[mgianzero]

Thanks for your prompt response.

Like I said, I am really interested in saving money on a day-to-day basis. That's why I thought of the intelliflow. But I am also concerned with cleaning at low flow. I have two skimmers. Should I turn one off and/or run at high flow (let's say an hour a day) to skim the surface. I can't image I can effectively skim at a very low flow, right?

My other cost is my pool cleaner. So I've abandoned my polaris and thought about a suction cleaner (thinking about Hayward Navigator vs. Barracuda). Or does it make more sense to buy a robotic cleaner and use it, say, once a week instead? Why do you say suction-side cleaners are more problematic? Is it because they require maximum suction to do the job right? If so, how much time (at maximum flow) should I start at? An hour a day?

 

[spishex]

Suction side cleaners are more problematic because of their dependence on your filtration system. Your Polaris was somewhat dependent in that it needed water flow, but it traps all the debris it carries in itself, and if it gets clogged up it just stops collecting. The suction side cleaner pulls all debris to a canister, skimmer basket, or the filter itself, just like if you were manually vacuuming. Thus when it gets clogged, your whole system suffers. I would consider switching from a polaris to a suction side APG a definite downgrade.

The robotic cleaner is a good option because it's completely independent of your system, but they're expensive and don't have the same rebuild-ability of pressure side cleaners, so once they're dead, they're dead. They do the best job of the lot but you pay for it.

You need about 15 GPM at each skimmer for them to work. As full speed pumps go, 30 gpm is pretty low flow. Do you have a main drain as well?

 

[mgianzero]

Suction side cleaners are more problematic because of their dependence on your filtration system. Your Polaris was somewhat dependent in that it needed water flow, but it traps all the debris it carries in itself, and if it gets clogged up it just stops collecting. The suction side cleaner pulls all debris to a canister, skimmer basket, or the filter itself, just like if you were manually vacuuming. Thus when it gets clogged, your whole system suffers. I would consider switching from a polaris to a suction side APG a definite downgrade.

The robotic cleaner is a good option because it's completely independent of your system, but they're expensive and don't have the same rebuild-ability of pressure side cleaners, so once they're dead, they're dead. They do the best job of the lot but you pay for it.

You need about 15 GPM at each skimmer for them to work. As full speed pumps go, 30 gpm is pretty low flow. Do you have a main drain as well?

I understand that suction-side cleaners can be a problem if they clog and you lose your system suction abilities. But I don't think this is much of a problem when I have two skimmers.

I do have several main drains (three total) but I can turn two off at a time if need be.

 

[spishex]

Not as much of a problem, but in many situations the skimmer with the APC connected needs to have more water flow dedicated to it to make the cleaner run properly which leaves the pump running mostly off that skimmer and susceptible to the problem I described. Multiple skimmers makes it more feasible but doesn't necessarily solve the problem.