Savings from switching from Single Speed to VSP (spreadsheet of costs included)

[jesse-99]

Three questions for your review.

So I've been thinking about this... ALL of my pumps are 230V single speed pumps. All currently working fine. It costs me roughly $380.00 per MONTH to run my pumps based on the my current usage (based on hours per day each pump runs, on average).

The biggest cost right now, and that's just because it runs WAY more than my other pumps is my main FP, so I'm considering replacing it with a Jandy VSFHP270DV2A variable speed pump (Jandy Variable Speed Pump 2.7 HP: Most Powerful Pool Pump | Jandy) . The ROI on the remaining 5 pumps would take me forever to recover, based on the minimal current utilization that I actual use them each day, so I'd probably only replace those as they fail.

Three questions.

1. I am TRYING to figure out, how much savings there would be with the Jandy VSFHP270DV2A variable speed pump. I see that it uses 2,250W at 10.5A, which I assume is at FULL RPM (barely less than my current single speed model). But I don't see anything in the Jandy specs or documentation that show my the Amps/Watts used at LOWER RPMs? (so I could calculate potential savings) --- How do I figure out, Amps/Watts at a lower RPM than MAX?

2. I'm not even sure I could run a VSP for my main FP at much lower RPM, only because my main FP provides for a) my 2 pool returns, but also b) my Caretake in-floor head system (37 heads, across 8 zones). I feel like lowering the RPM, might not let the in-floor heads pop up enough under pressure, and I might still need to run the VSP mainly at full RPM regardless, which would then negate any cost savings. Any thoughts on this one as well?

3. Am I wrong in thinking that the ROI on most of the other pumps (aside from my main FP in row 4) would take 10+ years to recoup and is only worthwhile if a pump fails?



I guess one nice thing about doing the spreadsheet is, since I used formulas, if I want to adjust a pump to run Y hours per day instead of X hours, now I can see how much extra $ / money that will cost me. Pretty handy.

 

[Rancho Cost-a-Lotta]

Here is a chart @PoolGate first posted a few years ago. I believe it's for a Jandy 2.7 HP VS pump...

 

[Kaylee34]

I can't help you with that particular pump and your calculations. That said, I wouldn't worry about the in floor pop ups. The beauty of the variable speed pump is that you can program it to run at different speeds on a schedule. You're not running those cleaners all the time so you only need to run the pump enough to satisfy them as needed. If you have automation, all this is even easier.

I bought my house almost a year ago to the day. The prior owner had the old single speed pump running on a mechanical timer 14 hours per day all day long, off at night and my electric costs were astronomical. My new variable speed pump is running 24/7 at 1500 rpm pulling 168 watts. When the bill comes this month, I'll post up the savings. I've already programmed a "winter schedule" that I'll switch to in November (I don't close) and I expect the cost will drop even more.

 

[jklocke]

My variable speed pump runs 24/7 at 1100 rpm and uses 88 watts - that's less than $10/month for me. My old single-speed pump cost over $100/month and only ran about 8 hours a day. I have better skimming, consistent chlorine production, and it's almost silent.

The chart from @PoolGate is pretty much right on for my Intelliflo. I agree that you won't get as much ROI from your other pumps. But now that you have your spreadsheet and know what each one is costing you every month, you have the info to decide if you just keep them or start replacing them too.

6 pumps is crazy! Is there any way to combine some of the water features so you could use a second VS pump to control them? You've probably already thought of that.

 

[jesse-99]

I just wanted to share this... Found this when digging into this a bit more. It was a surprisingly good read with some pretty helpful information.

https://www.nrel.gov/docs/fy12osti/54242.pdf

(1 snippet)

 

[HermanTX]

2. I'm not even sure I could run a VSP for my main FP at much lower RPM, only because my main FP provides for a) my 2 pool returns, but also b) my Caretake in-floor head system (37 heads, across 8 zones). I feel like lowering the RPM, might not let the in-floor heads pop up enough under pressure, and I might still need to run the VSP mainly at full RPM regardless, which would then negate any cost savings. Any thoughts on this one as well?

I suggest you create another Excel data set that only accounts for your FP. This is what I did for my new VSP, because it is unlikely you will run your Caretaker system the full time - you do now because you have a single speed pump - but with a VSP you will be able to schedule a block of time for in-floor cleaning and then other times for skimming or just circulation for chemical mixing.

Circuit Name	Hours	RPM	Watts	Total Watts
Pool	11	1750	263	2,893
P_Med	3	2350	674	2,022
Cleaner	1	2750	1077	1,077
P_Slow	4	2050	420	1,680
Cleaner	1	2750	1077	1,077
	20			8,749

Also, since you only run some of your other features from 1-3 hours a day - can you link them to a common pump and simply rotate a valve to which one is operating at whatever scheduled time? I guess the point is - do you really need an individual pump for every feature? It is a matter of convivence or is it required for design?
Do you have the waterfalls flowing into separate bodies of water where each needs its own pump?

 

[Kaylee34]

Bill is in. $193.62 less than last year for the month. The VSP will pay for itself in less than a year at that rate.

 

[randytsuch]

Wondering why you run your main pump for 20 hrs/day now?
Seems like a lot of run time.

As the others have said, you probably just need to run a VSP for some short time to clean the pool
The rest of the time, you will need to run it fast enough for your SWG to work, so fast enough for the SWG flow meter to sense flow. That depends on your pool, you'll need to experiment to find the speed that works.