A newbie whose disillusioned by VS pumps

[Mike1000]

Variable Speed pool pumps the pros and cons as I see them.

In 2019 my old single speed 110 V AC pump started leaking and had to be replaced. I was 'persuaded' that the way to go was by replacing it with a variable speed Pentair pool pump that cost around $1,000 as they allegedly would pay for themselves in a few years by savings on electricity bills. 3 years on I've seen little difference in running costs and for the past year a lot of aggravation with the old GFCI tripping. So far its cost me over $1,000 to get a new GFCI & Housing fitted next to the pump and new cable to the main panel to meet current code but the tripping issue is still present. So is the problem the pump ?

Here lies the problem that I see as, variable speed pumps cost a lot more than a 110 volt (or 230 volt) simple induction motor pump as first the 110 volts AC has to be rectified to 110 DC which is then used to power a variable frequency inverter (drive) that supplies an induction motor with a variable frequency & voltage drive depending on the selected RPM by the user. At stop the frequency is 0 Hz and there is no voltage but both parameters are ramped up to give a pump RPM of around 1500 RPM for low speed lower energy use for most of the time and up to 3450 RPM for high speed when cleaning the pool.

That's the advantages but there is one parameter that seems to be overlooked and that's the design of the inverter for pool pumps when GFCI's have to be used. Sold state inverters have been around a long time for battery back up with computers and its worth starting there to look at a potential downside. You can purchase 1500 VA UPS (Uninterrupted Power Supply) for around $200 that when your power goes off, you can run a desktop computer for up to 1 hour from a UPS which have 2 small lead acid batteries, a charger to keep them charged up and a fixed frequency/voltage Inverter to convert 12 Volts (or 24v) to 110 volts when main power goes.

The AC from your electricity company is a pure sine way and normally there is no 'noise' or interference present that affects any household equipment. In rare cases, one can fit line filters to clean it up if there's a problem. However, inverters are 'noisy' by nature due to the fact that the simulated sine wave is created by high power semiconductors turning a DC voltage on and off at different levels, intervals and different points along the 360 degrees of a sine wave. Whilst power from the electricity company comes from from turbine/generators and produces a perfect sine wave, the simulated sine wave from inverters is a 'stepped' sine wave and that produces noise. For most appliances, like phone/tablet chargers, computers, lap tops, TV's, Hobs, Ovens etc the noise has no effect, however there is some anecdotal evidence that noise from the pumps inverter might trip GFCI's. It should be noted that pump inverters that vary their frequency output will produce 'noisier' sine wave at lower RPM (frequency) than at a higher RPM or frequency.
The rated power of this pump is claimed to be a max of 12 amps or so, far more than one used in a UPS which always runs at 60 Hz anyway.

So far I've tried new cabling, a new GFCI, ferrite noise suppressors on the 3 wires between the pump and GFCI and still it trips at random every day or so. Perhaps if this Pentair Pump remembered the time I could live with it but like Microwave ovens it doesn't remember the time.

One other oddity is when the pump first comes on in the morning. Its supposed to go full speed at 3500 or full speed to prime the pump and then go to program 1 of 3. It does that as the RPM drops to 2500 which I have it set for but a few minutes later the pump will stop, wait 10 secs or so and then ramp up again. It may repeat this for 3-5 times before settling down and running normally unless a random trip happens.

I've had two attempts to get answers from Pentair about this odd behavior with no explanation and as far as the GFCI is concerned I've got nowhere. A blog site reports similar issues over the GFCI with claims that Pentair recommend Siemens GFCI's rather than Squard D GFCI's. The response I got from Pentairs support site over GFCI's was -

"Also regarding the breaker we do test all units with siemens breakers and they work the best for our units. we highly recommend using the, and the correct size as well"

Needless to say there was NO warning to use Siemens GFCI's rather than SquareD in the installation guide and their response doesn't highlight a problem with SquareD.

In conclusion -

Is it a GFCI incompatibility issue ? I don't know and Pentair refuse to comment !

Have the electronics gone crazy in the Pump ? It might be as the tech guy couldn't explain that peculiar start up sequence where it started and stopped for no reason.

So, I'm junking this over prices and worthless VS pump and fitting a simple 2 speed pump at 1/3rd the cost and while I'm at it, I'll have installed an Alexa ready Wi-Fi timer at waist height instead of getting down on my knees to use the crappy key pad that's on the pump. At least I can use my phone to change times if needed.

I forgot to mention, its a very noisy pump this Pentair pump compared to the ancient one that died in 2019 after giving good service. If anyone knows of a fix or suggestion, I'd welcome it.

Thanks - Mike

Update on my issues with a Pentair Intelipro VS pool pump, this what I found.

With the help of a plumber and electrician we took out the Pentair pump and fitted a Blue Wave NE6181 Tidal Wave 2-Speed Pump ($303) in its place and added a Alexa compatible wi-fi pool scheduler timer ($80) as well as a flow meter ($70) to check on the real performance.

At low speed of 1750 RPM with a freshly cleaned clean filter I got 20 GPM flow with a power consumption of 2.5 amps (300 watts measured with a clip on amp/watt meter. With my 10,000 gallon pool that's 500 minutes or 8 hours to cycle the pool water once.

At high speed of 3450 RPM for cleaning the pool, I got 40 GPM flow (not unexpected for twice the RPM) at 3 times the power consumption of 900 watts. Again, pleasantly surprised as articles I have read suggested 4 to 5 times the power than low speed operation.

So, assuming my calculations are correct at 7 cts a kilowatt hour and for 8 hours low speed running, that's around $5 a month plus another $4 for the year when cleaning at high speed.

The only caveats I can think of depends on these other factors -

1 - If the water quality is not good enough with just 8 hours at low speed, I''l try 12 hours and then 16 hours

2- Summer months may require slightly longer running but its a case of trial and error.

3- Right now I'm getting a lot of pollen in the pool which clogs the filter within 2 days or so and reduces the flow significantly. I'll just have to clean it every 2 days (a 10 minute job) to keep the 20 GPM flow going. for the next week or two.

As for the old Pentair pump, unscrewing the top panel to disconnect the power cord showed us that a small amount of water was present inside the electronics area and the 120 Volt connectors. Its almost certain that was causing the GFCI tripping. Additionally, the new pump was so quiet at low speed you could hardly hear it and even at high speed it was only a faint hum. In contrast the Pentair made a real racket at high speed. and was still noisy at a lower speed of 1500 RPM. Maybe a seal or bearing was shot causing this as well as the water inside it or maybe its because of the synthesized variable frequency & voltage is non pure sine wave.

Either way its looking good now with enough flow, low power consumption, very quiet and one third the price of a VS Pentair pump.

 

[Mdragger88]

Mike,
Very interesting data
You don’t have your signature filled out with all your equipment & I don’t recall from your previous post but it sounds like your filter is undersized. Using some of your savings from going with the 2speed to upgrade your filter may be very beneficial for you, even more so than having a vsp.
Cleaning the filter every two days sounds like a nightmare.
Everyone isn’t always better served by getting a vs pump over a 2speed economically. That sounds like the case here. It’s one of those things that’s nice to have if you can afford the initial investment type of things. That said, either one is a vast improvement for energy consumption vs a single speed pump. Those who operate a swg & like to skim all the time whilst chlorinating generally benefit the most from investing in a vsp & have a quicker R.O.I. from it.
It also sounds like the pentair vsp had some issues that most don’t have which is a bummer, hopefully things will go swimmingly with its replacement

 

[JoyfulNoise]

Sounds like a good end to the story. Hopefully the BlueWave will go the distance. I’m not a huge fan of Chinese manufactured equipment but, for $300, you really can’t beat the price.

As for the IntelliFlo and water incursion, it’s been seen in the past as a potential failure mode. I think Pentair, like other manufacturers, have had lots of issues these days with reliable assembly of their equipment and their warranties are never good enough to cover these events. Which is sad because, in general, Pentair is a well respected brand name and they only hurt themselves when they let lemons flood the marketplace.

 

[Mike1000]

Mike,
Very interesting data
You don’t have your signature filled out with all your equipment & I don’t recall from your previous post but it sounds like your filter is undersized. Using some of your savings from going with the 2speed to upgrade your filter may be very beneficial for you, even more so than having a vsp.
Cleaning the filter every two days sounds like a nightmare.
Everyone isn’t always better served by getting a vs pump over a 2speed economically. That sounds like the case here. It’s one of those things that’s nice to have if you can afford the initial investment type of things. That said, either one is a vast improvement for energy consumption vs a single speed pump. Those who operate a swg & like to skim all the time whilst chlorinating generally benefit the most from investing in a vsp & have a quicker R.O.I. from it.
It also sounds like the pentair vsp had some issues that most don’t have which is a bummer, hopefully things will go swimmingly with its replacement

Hi, This pollen issue is just a short term event of around 1-2 weeks as we get it each year late Feb early March. I'm surrounded by Florida Oaks from neighbors trees that dump leaves in the pool for 6 weeks or so, then the pollen starts and at the same time what we call 'coffee grounds' in Florida from these trees. This winter we covered the pool with netting to catch the leaves but it doesn't stop the pollen or the finer 'coffee grounds', both should be over by mid march. My objective was to try and balance out maintenance effort, with energy consumption and installation costs. The filter was increased in size by a factor of 2 when the Pentair pump was fitted compared to the previous failing 1 HP single speed pump that was there when we bought the property. It was more than adequate until the pollen arrived.

Had the Pentair pump not developed a leak that seems to have tripped the GFCI intermittently, I wouldn't have looked at this to the degree I have. One major plus point I now have is I can monitor the status of the new pump (on or off) from anywhere around the house or yard and setting the daily schedule is a breeze from my Android phone using Smart Life or even Alexa. Previously, it was a pain in the rear literally sitting balanced on a chlorine tab tub to use the Pentair touch pad and trying to see what the crappy LCD display was showing. The GUI or set up was not user friendly or intuitive and the touch pad wasn't that reliable either. I did contemplate getting a Pentair remote that can plug into the pump electronics but the documentation of what it would or wouldn't do was vague and they wanted around $500 for it. Now I have a more user friendly wi-fi set up for $80 from Amazon to add to my other Alexa devices like lights, security and my A/C. I even have spare 'remotes' like older smartphones that are no use for 5G phone use but are more than adequate as additional spare remote devices.

Anyway, thanks for the interest, Mike