Sta-Rite 1.5hp variable speed replacement

[LutherKrank]

Hoping to find a solution to 70% of my energy bill going to my pool equipment. I have a Sta-Rite Max E-Pro 1.5hp P6E6F-207L / 230v 10.4a, along with an PB-4 3/4 hp, 230v, 6.4a booster for a Polaris 280 sweep. I'm in Central California and PG&E is electrical supplier with tiered rates, which means I'm at .32/kwh after about the second day of the month.

My original idea was a Pentair Intelliflow or Hayward Eco-Star, or maybe an EcoPump EP-8 3hp(variable speed), and get rid of the booster. My wife's uncle down the street has an Intelliflow and it is awesome, running low it pulls about 120w of power. At full blast, which is all the time, I'm pulling about 17 amps or about $1.25/hr. The pool has 1-1/2" plumbing, and my local pool guy and the Hayward rep are both saying the 3hp variable's won't work because they require 2" plumbing. They're both recommending a Hayward SuperII pump, single speed. I'm sure it's a little better, but at this point, I'm obsessed with lowering my cost of operation, I'll happily spend a grand or two to pay myself back in a year.

Hayward also has a Max-Flow VS and a Super Pump VS that say they'll work with 1.5" plumbing. I'm sure the Super II is a fine pump, but my primary goal is to quit watching my power meter for thrills(chills more like it).

Any assistance much appreciated.

Luther(Chris in CenCal)

 

[jblizzle]

Welcome to TFP!!!

Hayward also has a Max-Flow VS and a Super Pump VS that say they'll work with 1.5" plumbing.

These are pretty new to the market but appear to be VERY nice smaller VS pumps that should work great for your application.

There have been discussions in the background of the forum of starting to recommend these pumps when the large VS pumps are overkill, like your situation.

The other option would just be a new 2-speed motor to put on your existing pump and then running on low speed, but honestly, with your electrical cost, I think you would be very happy with one of the smaller VS pumps.

If you go that route, please be sure to report back as we are very interested in getting some real world feedback.

EDIT: one thing to note though, those VS pumps are smaller than your current pump, so on high you will not get as much flow. I just noticed your solar setup ... which of course are more efficient at heating at higher flow rates. But you will save significantly by running at low RPM when solar is not required.

 

[JasonLion]

Welcome to TFP!

No single speed pump should be considered under any circumstances, that is just silly. If minimizing up front costs was an issue you could consider a two speed pump, but even that wouldn't be worth it in the long run.

The IntelliFlo and EcoStar pumps are both highly regarded pumps that are quite efficient and both will work fine in your situation (with some minor setup on their configuration menus). Stay far away from the EcoPump.

You only need 2" plumbing for several inches on either side of the pump. Adapting that down to 1 1/2" pipe for the rest of the plumbing run is just fine.

The Hayward Max-Flo VS is certainly worth consideration. It is brand new, so we don't have reliability information just yet. But it is less expensive than the other two and in some ways a better fit for your situation.

 

[LutherKrank]

Wow, am I glad I found this place. Thanks so much for the replies. I'm interested in the theory that I could just alter the plumbing as long as the 2" extends a certain distance in that I could go to an Intelliflow or EcoStar, but if there are finally VS pumps for 1.5", that'd seem better. By the way, I had found the EcoPump and even spoke to the president of the company I guess one day. What's the issue with them, I've seen some rather poor reviews here. As to my solar heating, I doubt it gets used more than a month a year total, and was designed pretty neatly. It's on it's own structure, and the lift is only maybe a couple of feet, although it is probably 60'+ feet long and then back through.

I'm going to call my local guy and see if I can get the Hayward rep's number and ask him more specifically if they'll work. It's funny, I live in a bass-ackward town, and I've been to Leslie's and another equipment dealer, and both said I know more than they do about variable speed pumps. I'm a darn glorified accountant, not an engineer, didn't fill me with warmth about their knowledge and ability to help me.

 

[jblizzle]

With the larger VS pumps, you will not want to be running them anywhere near full speed as your plumbing is just too small. What Jason was saying is that you would just have to increase the pipe size near the pump so that you could connect it to your smaller plumbing.

Although these pumps do seem to like to have a good 12" of straight 2" pipe entering the front of the pump to avoid some issues that have been posted on the forum.

 

[LutherKrank]

Any ideas if such a pump would eliminate the need for the additional booster for the Polaris like the Intelliflow and Eco-Star?

 

[jblizzle]

The 280 requires a booster pump regardless of the main pump you have ... that is the way they are designed.
There are different pressure cleaners that can be used without the booster pump, but the 280 is not one of them.

 

[LutherKrank]

Is the 2" vs 1.5" plumbing coming into the pump determining what's referred to as "head"? I'm trying to evaluate the two Haywards, and the performance, i.e., gpm is different at different rpms and the measurement is x head y gpm or vice versa if that makes sense, I can't remember a darn thing from graphs and all that. The Max-Flow VS seems a little more capable than the Super Pump VS, but is a little cheaper, obviously a different design on some level although they share the same 230v 5.9a motor.

 

[LutherKrank]

I'm now seeing that Hayward has a supposedly more efficient (claim is 40%) 3/4 hp booster, I presume it would only be more efficient due to a more efficient motor. Are all of the TEFC motors just that more amp efficient if that is a term, lower amps, moves more or less the same gpm at full speed, but as the rpm goes lower, the power seems to drop more than the % of rpm drop. But if it's just a 3/4 hp, single speed, how do they get the efficiency? My terms could be all wrong, again, I crunch numbers all day, but not this kind.

 

[jblizzle]

No. The head is a combination of all the resistance to the water flow (pipe size & length, number of suction lines and return lines, number of fittings, filter, heater, eyeball sizes, etc) It is not easy to determine the headloss.

I really think those 2 are pretty similar. Just looking at the pump curves, the Max-Flow does seem to move a little more water at the same head loss.
What that means though is that the Max-Flo will move the same amount of water at a lower electrical cost than the SuperPump.

So, if the Max-Flo is cheaper, I would get that one.

 

[JasonLion]

"Head" varies with all kinds of things. It is a measure of how much resistance to flow there is in your plumbing. At higher water flow there is more head, ie more resistance. When pipes are smaller there is more head. When pipes are longer there is more head. And the more fittings you have, the more head there will be. Figuring out head is quite complex and almost never worth the effort.

Some motor designs have higher inherent efficiency than others, though the differences are generally small. In the pool industry, when talking about single speed pumps, a "high efficiency" motor/pump is generally about 10% better than a regular motor/pump. The high efficiency versions cost more, so they keep selling the low efficiency version.

Some of the variable speed pumps have even higher inherent efficiencies, about another 10% improvement.

However, the largest factor that effects efficiency is how large the pump is. Higher flow rates mean more resistance to flow (friction essentially) and thus lower efficiency. However, this does not really apply to booster pumps, as they generally all move the same amount of water.

Variable speed pumps are kind of a special case, as running at a lower speed is much like having a smaller pump. So lower speeds are more efficient. That does not continue forever. Below a certain speed you lose too much energy to various fixed energy drains (wire resistance, bearing friction, etc) and they stop getting more efficient, but the general rule still works most of the time.