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Katy-Texas
03-26-2006, 08:39 AM
Advice please, new to pools, had ours (~26,000 USG salt water) 10 months now. Power rates here in Texas went up ~50% this winter, not looking forward to power bill for AC & pool this summer !

Read tips on www.poolsolutions.com including one on mail filter pump HP and power costs, I have "standard" 2.0 HP main filter pump (Pentair WhisperFlo Model WF-28, Service Factor = 1.1) and probably small plastic lines between pump and pool and thus high backpressures due to friction et al. Not good.

1) Curious (as too late to change), how do I measure pipe sizes is it OD or ID?

2) To reduce power cost assume I assume not worth changing this "big" pump out as less than 1 year old?

3) Water circ back to pool via white plastic nozzles at sides of pool and in spa that are screwed onto the plastic pipes. Seems to me that if I removed these nozzles then back pressure would be significantly less and thus pump volume would be significantly higher and thus I could run pump less per day?

4) OK so removing nozzles would be unsightly, how about I just drill them out to 1" holes?

5) Any other power saving ideas?

Thanks in advance . . .

Jimmy C
03-26-2006, 11:05 AM
I live in Round Rock Texas, and last fall I switched from TXU to "Direct Energy". The rates from the same pole are about 20% lower after the switch.

Also see my post in this section about 2 speed motors. Upgrading to a 2 speed motor will have a fast payback period. Just increase your pump on time to move the same volume of water every day. Look at the curves on competitive pumps. Lowering the pump backpressure at low speed helps the water flow better, so the GPM reduction at low speed is not nearly as dramatic as the speed reduction of your electric meter.

Use high speed for extra skimmer suction, bottom feeders, vacuuming, but not every day.

Just pay attention to the low speed priming issue.

I think that this 2 speed motor idea is as big a secret as using bleach, borox, and baking soda as compared to a dump truck full of chemicals ($$$$) from the pool store.

Jim

Katy-Texas
03-26-2006, 03:49 PM
Jim, thanks for support.

Power supplier, good point, I live in Katy Texas and used www.powertochoose.com and my zip code to compare power rates and switched from Reliant to Gexa Energy which is also is cheaper I think than Direct Energy, plus wehen I signed up for auto monthly billing against my credit card they gace me 2000 Continental Airmiles plus airmiles for each monthly charge. Problem is all the providers rates went up significantly :mad: this winter.

mwsmith2
03-26-2006, 09:50 PM
I live in Katy Texas

Not to threadjack, but howdy neighbor! :D

Michael

mas985
03-27-2006, 11:30 AM
Answers to your questions:


1) Curious (as too late to change), how do I measure pipe sizes is it OD or ID?

ID but usually not exact to the pipe size.

2) To reduce power cost assume I assume not worth changing this "big" pump out as less than 1 year old?

It could still be worth it. Especially if you can get a rebate from the power company. Some states offer up to $300. Even so, pay back could be less than 2 years.

3) Water circ back to pool via white plastic nozzles at sides of pool and in spa that are screwed onto the plastic pipes. Seems to me that if I removed these nozzles then back pressure would be significantly less and thus pump volume would be significantly higher and thus I could run pump less per day?

Yes, you could first try to remove them and see if your pressure gauge drops.

4) OK so removing nozzles would be unsightly, how about I just drill them out to 1" holes?

You may want to see if you can purchase new fittings first. If you cannot, then consider drilling them out. Most returns are 1", so it seems odd that they are so small.

5) Any other power saving ideas?

My guess is your turnover rate is about 3 hours? If so, try running the pump for only 3 hours a day. 6 during heavy swimmer loads.


Mark

Poconos
03-27-2006, 12:04 PM
Just a simple thing and not very significant. When the pressure increases the power consumption (current) to the pump decreases. Try putting a clamp-on ammeter on the pump line and see what happens. Look at the current (amps) full flow then blocked. Turns out that when the flow is totally blocked the power consumption is at a minimum. No water flow = no work done = low power consumprion. Specific to a centrifugal pump. On to the issue....I bored my return nozzles out to cut the pressure but I also know I don't have to run the system as long and therefore save some energy. Me thinks we're talking details that won't make much difference in the monthly $$ electric bill. As much as I'm being a monkey and tracking all this stuff, I haven't done it for this issue. So.....just my thinking and fodder for discussion.
Al

CarlD
03-27-2006, 01:29 PM
Good suggestions! 2 speed pumps are the way to go! How many gallons is your pool? 2hp sounds HUGE. I run a 20,000 gallon pool with solar heat on a 1 hp Super Pump (Hayward) and I run it on low-speed 99% of the time.

bell7272
03-27-2006, 04:48 PM
Now I'm concerned about my pump.

Our pool is close to being done and the builder has a 2.5 HP Hayward Super 2 pump setup.

We have a Hayward DE 6020 Filter. A Rock waterfall, 3 foot shear decent fall, 4 returns, 2 spa jets (in pool), skimmer and vac line. Will be getting solar later this year (9 - 10 panels).

Pump is same ground level as pool and furthest point away from pump is maybe 100 feet. PVC pumbing is 2". Pool also is 15 X 30 freeform but only 3 ft to 5.6 feet deep. I'm guessing gallons at maybe 13K.

Should I have builder take out pump and replace with smaller, or can I (as some said in this thread) simply run the pump for only 3 hours a day.

I should also say salesman told me I "didn't" want a 2 speed pump when we were getting started.

Thanks for any advice.


W Bell
Orlando, FL

mas985
03-27-2006, 06:22 PM
Because of the water features and vac line, you will need heavy flow some of the time. This means you have two choices, multiple pumps or a 2-speed pump. For a 2-speed pump, the turnover time is twice as long as that of the high speed but the energy use is about a third. So overall energy savings is about 30%. Going form a 2.5 Hp to a 1 Hp pump will save you close to the same (depending on pump) but you may still need a bigger pump for the features and vac. So either way, you should have significant savings which will pay for itself in not too much time at all.

kaybinster
03-28-2006, 11:58 AM
If your utility offers it, you might want to switch to time of day billing. Obviously you will need to do an analysis of how much electricity you use at various times of day. In NJ, time of day billing gives you cheap power during off-peak in exchange for expensive power peak periods which are M-F 9am-9pm. I have an electric heat pump to heat the pool and run the pump and the heat pump at night and on weekends when power is cheap.

Another option is to install a PV solar electric system to generate your own power. I have a 10 kw system which generates about 12,000 kwh a year. Check out the threat on solar water heating where I described the system in more depth.

bell7272
03-28-2006, 12:04 PM
OK, Thanks.

If I would keep the pump, then can I simply run the pump /filter less time than I would with a 1 HP. Say 3 hours versus 6-7 hours.


Thanks again.

slowtan
03-29-2006, 05:23 AM
I thought you are suppose to run your pumps when it is during the hottest part of the day???


If your utility offers it, you might want to switch to time of day billing. Obviously you will need to do an analysis of how much electricity you use at various times of day. In NJ, time of day billing gives you cheap power during off-peak in exchange for expensive power peak periods which are M-F 9am-9pm. I have an electric heat pump to heat the pool and run the pump and the heat pump at night and on weekends when power is cheap.

Another option is to install a PV solar electric system to generate your own power. I have a 10 kw system which generates about 12,000 kwh a year. Check out the threat on solar water heating where I described the system in more depth.

Katy-Texas
03-29-2006, 08:49 AM
Wow this thread got active during my absence.

1) MWSMITH2 - Howdy neighbor, I’m in Grand Lakes subdivision.

2) mas985 – Thanks for your response to my thread starting questions, I have a 1 foot raised spa with spillover so probably the builder was by installing small nozzles, trying to ensure water diverted to spa, and thus spillover. I’ll try fully removing the “nozzles” one at a time to watch what happens to spa spillover. Also thanks for your thoughts on pump economics.

3) Poconos, agree, centrifugal pump, dead head pump and very low current draw. Same pump curves for big electric submergible centrifugal pumps we install in oil wells, however for those pumps there is a sweet spot range that the pump is designed for, too low a rate and yes low power but pump in downthrust (ie wrecks bearings), two high a rate vs design range and pump in upthrust, same problem. Problem is that what I want is high volume per $, or rather high volume per amp. So I assume this is when rate is highest (haven’t looked at pump curves)?

4) CarlD – My pool is ~26,000 USGallons, is your Hayward Super Pump a two speed pump or do you just run it full at 1 HP?

5) Slowtan - I read somwhere, I think www.poolsolutions.com tip that better in my case (saltwater pool) to generate Chlorine in evening as thus longer for it to do it's work before sun burns it off again next day . . .

Reason away is it's been garden planting season around here in South Texas, especially as it’s been unusually cool, pool dropped from 72 F two weeks ago to 61 F . . . . back to heating the spa ! ! :D

CarlD
03-29-2006, 04:33 PM
My super pump is 2 speed and I run it at low 95-99% of the time--with solar panels. But my pump is close to the pool, and the panels are the deck around the pool (nice! The deck stays cool to walk on !)

I don't know all the math but I suspect a 2.5hp pump is too darn big for most pools--but the spas may need it.

With 26k, you can go with a 1.5 superpump 2 speed and STILL get great performance in low speed.

mwsmith2
03-30-2006, 08:55 AM
If your utility offers it, you might want to switch to time of day billing.

Yeah, down in this part of the world, we don't have such a thing. Ah well. Even if that were possible, I'd still want to circulate during the hottest part of the day to keep the Cl levels constant throughout the pool, especially since I have a SWC.

Michael

kaybinster
03-30-2006, 09:47 AM
Yeah, down in this part of the world, we don't have such a thing. Ah well. Even if that were possible, I'd still want to circulate during the hottest part of the day to keep the Cl levels constant throughout the pool, especially since I have a SWC.

Michael

Always thought you wanted to chlorinate after the sun went down to minimize the sun burning it off. I have done this now for 8 years and have never even once had a problem with any algea or any other water problems.

CarlD
03-30-2006, 09:55 AM
Always thought you wanted to chlorinate after the sun went down to minimize the sun burning it off. I have done this now for 8 years and have never even once had a problem with any algea or any other water problems.

Apples and oranges.

Michael is talking about circulation when the water is most at risk, and, with an SWG, all is different.

Adding chlorine after the sun sets allows the chlorine to fight the algae without risk of it being broken down too soon by UV light.

As for your pool, sounds like it ain't broke--so you have no reason to fix it.

mwsmith2
03-30-2006, 10:07 AM
Always thought you wanted to chlorinate after the sun went down to minimize the sun burning it off. I have done this now for 8 years and have never even once had a problem with any algea or any other water problems.

Well, if you use CYA, there's really no worry about having the sun burn it off. I agree with Carl, if it works for you, no need to change!

Michael