Posted By eddysaad on 11 Oct 2016 02:35 PM
The other great advantage is NOISE level is gone. Before, i would just have to open the basement door to know that the pump is running. Now, not even close!!!

Sounds like VFDs are the way to go. The power savings and advantages are well noted.

Posted By Lbear on 12 Oct 2016 01:48 AM

Posted By eddysaad on 11 Oct 2016 02:35 PM
The other great advantage is NOISE level is gone. Before, i would just have to open the basement door to know that the pump is running. Now, not even close!!!

Sounds like VFDs are the way to go. The power savings and advantages are well noted.

Only time will tell. Most times the pain is not worth the pleasure. Anything that seems too good to be true usually is. I have been replacing VFD's with CSV's for nearly 25 years now. Most people will give up the efficiency of a VFD for the reliability and lower cost of a standard pump/motor system. While most pump installers are still eager to install VFD systems for their customers because of the greatly increased profit margin, most are going back to a standard single phase pump in their own homes. Most have tried several different models of VFD's over the years. While they may have their own hoist truck, special tools, and a store room full of pumps to use, it is still no fun to wake up to no water coming out of the faucet because of some technical complication. The simpler the pump system, the more likely water will come out of the faucet when needed. I wish you the best of luck though.

Posted By jonr on 06 Jul 2016 12:42 PM
  On the other hand, my opinion is that Valveman should always disclose his commercial interest when discussing his CSV - without being prompted.

Interesting. So he sells CSV's and therefore disparages VFDs.   It's like asking MSNBC to give a balance and unbiased view of Trump.

Modern VFDs are not like those of yesteryear.

1980's carburetor cars are less reliable than a modern fuel injected vehicle. Technology advancements have made modern cars very reliable, efficient and long lasting. Just like modern VFD's.

An on/off pump works fine on an irrigation system that stays on for hours or days on end. VFD's work better on house designs since they are low water intermittent usage.

See below

Posted By eddysaad on 04 Oct 2016 03:45 PM
Nathan, you inspired my project and i just installed a PID20 as well - so thank YOU. i was looking for this information for a long time and your data convinced to do the same. I had the CSV setup, however, it did not drop amp at all - barely any!!!. I have a 5 ton multistage geothermal which requires variable water flow rates ranging from 5 to 18 gpm of course at the lowest possible PSI. I have 3/4 HP pump and it was drawing 7 AMPs now i'm down to 1.9 amps (significant improvement). The CSV was great at maintaining the pressure, but not lowering power usage by much. I will also be using the second setpoint for irrigation.

Have you connected it to grap telemetry data ? if so how?

That's great it was able to help you out! Are you using the run enable function of the Intellidrive? I actually encountered a bug in their firmware in the run enable code, which causes the VFD to cycle the pump on and off briefly for about five minutes, saying no flow - even though the run enable circuit was open (should have stopped pump).

With regards to power factor, my watts are adjusted for power factor - I use a GEM energy monitor - (http://www.brultech.com/greeneye).

Lastly, valveman, good job being objective with the discussion here, I'm impressed!

Nathan

Posted By Lbear on 13 Oct 2016 01:32 AM

Posted By jonr on 06 Jul 2016 12:42 PM
  On the other hand, my opinion is that Valveman should always disclose his commercial interest when discussing his CSV - without being prompted.

Interesting. So he sells CSV's and therefore disparages VFDs.   It's like asking MSNBC to give a balance and unbiased view of Trump.

Modern VFDs are not like those of yesteryear.

1980's carburetor cars are less reliable than a modern fuel injected vehicle. Technology advancements have made modern cars very reliable, efficient and long lasting. Just like modern VFD's.

An on/off pump works fine on an irrigation system that stays on for hours or days on end. VFD's work better on house designs since they are low water intermittent usage.

No, I "disparage" and replace VFD's with CSV's because I know them both very well. I studied electrical engineering in the 70's and started using VFD's in my pump business in the 80's. The statement you make about "modern VFD's are not like those of yesteryear" is the same statement the manufacturers of VFD's told me in the 80's, 90's, 2000, 2010, and even still today. And yet they still have not been able, and will never be able to fool mother nature and perfect the idea. But they have gotten better. And I don't disparage all VFD's, just those used on systems that could be better served using something else. I have VFD's on some of my plastic injection machines that work great. They work so good with the positive displacement hydraulic pumps that I don't even mind having to keep the cabinet door open and having an air conditioner pointed at them to keep them from tripping out from overheating. But water pumps are not positive displacement and are not usually in a location that allows an air conditioner to keep the VFD cool. I actually love VFD's. Since my business is replacing them with CSV's, the more VFD's people try the better. And if VFD's really worked as good as advertised, I wouldn't still be in business replacing them everyday. I am happy for the people who can make VFD's work properly and last a while, but I am here for the many that it doesn't work out for. Sure I sell a competing product, which is why you will hear the truth from me. You will only hear the fluff from those who sell VFD's, as they make a lot of money on them.

Based on Franklin's figures, I'd guess that any 1 HP well pump drawing 1800 watts was exceeding its service factor and was going to see reduced life.

Posted By jonr on 13 Oct 2016 11:30 AM
Based on Franklin's figures, I'd guess that any 1 HP well pump drawing 1800 watts was exceeding its service factor and was going to see reduced life.

1HP equals 745 watts. But submersibles run at about a 1.65 service factor. So 1229 watts should be max for a 1HP.

Posted By Valveman on 13 Oct 2016 11:42 AM

Posted By jonr on 13 Oct 2016 11:30 AM
Based on Franklin's figures, I'd guess that any 1 HP well pump drawing 1800 watts was exceeding its service factor and was going to see reduced life.

1HP equals 745 watts. But submersibles run at about a 1.65 service factor. So 1229 watts should be max for a 1HP.

As per the Pentek Intellidrive manual a 1hp 230/240v motor has a SFA of 8.1 (8.1*240=1944 watts). I believe mine was slightly less at 1800watts. This also aligns with motor manufacturer's ratings. Also, when the VFD kicks into full speed (60hz) I see 1800w+ on it's display, then drops to ~400watts at 31hz. Nathan

SFA of 8.1 (8.1*240=1944 watts).

Does the pump manual actually say "1944 watts" or is power factor being left out again? I estimate more like 8.1*240*.85 = 1652 watts. Consistent with Franklin's 1600 watt max load for a 1 HP pump.

See below attachments. Control box has SF is 1.4 and amp 8.2 (SF Max amp is 9.8) 1HP. Manufacturer's motor spec lists FL amps 8.4 with SF amps 9.7. Maybe someone can explain why the differences vs traditional hp watts.

From here we see a max SF watts of 1672 for your motor and control box. It's best to operate pumps at well under the SF maximums - maybe the Intellidrive can limit peak watts.

Hey Nathan, after the install, the first thing I did is upgrade to the latest firmware. I had an issue with pump recycling every 90 seconds. I called Pentek support and they did suggest to increase the delay boost times and that resolved the issue. Time will tell what my actually saving are, i guess a couple of months of usage and comparing to last year will help. I stayed away from the Franklin and Gould's drives because they lacked the digital sensors and no display. are you able to capture any data from the drive? if so how? what i'm trying to do is connect a raspberry pi or something and capture drive data and merge it with my Waterfurnace data.

@valveman, for house water, I would definitely recommend the CSV for many of the reasons you stated, I did actually recommended CSV to a friend who has an issue of varying pressure. HOWEVER, For newer Geo units that run multistage and require varying flow rates and extremely low pressure, VFDs are the way to go.

Posted By eddysaad on 14 Oct 2016 02:00 PM
Hey Nathan, after the install, the first thing I did is upgrade to the latest firmware. I had an issue with pump recycling every 90 seconds. I called Pentek support and they did suggest to increase the delay boost times and that resolved the issue. Time will tell what my actually saving are, i guess a couple of months of usage and comparing to last year will help. I stayed away from the Franklin and Gould's drives because they lacked the digital sensors and no display. are you able to capture any data from the drive? if so how? what i'm trying to do is connect a raspberry pi or something and capture drive data and merge it with my Waterfurnace data.

@valveman, for house water, I would definitely recommend the CSV for many of the reasons you stated, I did actually recommended CSV to a friend who has an issue of varying pressure. HOWEVER, For newer Geo units that run multistage and require varying flow rates and extremely low pressure, VFDs are the way to go.

When the pump is way over sized, a VFD will reduce the electric consumption fairly well. But the VFD system will still be using more energy than a pump working at its best efficiency point and sized correctly for the flow and pressure needed. Being able to run at 31hz is a sign the pump is way over sized for the demand. And since 30hz is the minimum speed that is supposed to keep the film of water needed on a Kingsbury thrust bearing, I would be very hesitant to run at 31hz. Sometimes it is hard to size a pump for the demand when there are multiple demands, which a VFD can help with. But as you can see, even after 50+ years of trial and mostly error VFD's still have "issues" requiring "firmware updates" and other patches. I think you will find the reason there are so many "newer versions" of VFD's, is because there are many un-fixable problems with the older models. Everyday someone says to me that "it doesn't matter how much energy my heat pump and VFD system are suppose to save if the pump system doesn't last long enough to pay for itself". Please keep us updated on how things are working as I would be very interested to know what you think in 5-10 years.

It would be interesting to see a good energy comparison of a single over-sized pump plus VFD pumping two pressures (eg, 15 psi and 60 psi) vs a smaller pump plus a second booster pump. At thousands of hours per year, the difference might be significant.

It's also interesting that CentriPro recommends using their CSCR (capacitor start/capacitor run) controller for better efficiency.

Posted By eddysaad on 14 Oct 2016 02:00 PM
Hey Nathan, after the install, the first thing I did is upgrade to the latest firmware. I had an issue with pump recycling every 90 seconds. I called Pentek support and they did suggest to increase the delay boost times and that resolved the issue. Time will tell what my actually saving are, i guess a couple of months of usage and comparing to last year will help. I stayed away from the Franklin and Gould's drives because they lacked the digital sensors and no display. are you able to capture any data from the drive? if so how? what i'm trying to do is connect a raspberry pi or something and capture drive data and merge it with my Waterfurnace data.

@valveman, for house water, I would definitely recommend the CSV for many of the reasons you stated, I did actually recommended CSV to a friend who has an issue of varying pressure. HOWEVER, For newer Geo units that run multistage and require varying flow rates and extremely low pressure, VFDs are the way to go.

Eddysaad, the only data I am capturing from drive is via CTs on my home energy monitor. I don't have it linked to anything for automation/alerts. There is a serial interface I believe but think Mfg told me it was for future use. Anyway, as for sizing, just make sure you have enough flow by water jacket to cool motor (depending on well diameter etc - it needs a minimum linear feet of flow to dissipate heat). At 14 GPM on mine even at 31hz and a 6" well this was enough according to pump motor manual. I have boost set for 5 minute IIRC so after flow is shut off at heat pump, pump continues to run for 5 minutes without flow - which I don't like. I would have preferred to use the run enable function to control VFD on/off, but it isn't reliable due to bug unfortunately. Nathan

Maintaining 1/2 foot per second flow across the motor is important, but at 31hz I am concerned about the internal flow across the thrust bearing. It takes a minimum of 30hz to create the film of water between the thrust pads and plate. Without that hydroplane effect a thrust bearing isn't going to last very long. Running 5 minutes at zero flow is a different issue but is not good for the motor either.

I installed my open loop geothermal heat pump system several years ago and it has been working fine summer and winter ever since.  I have a 20 plus gpm well for water supply and installed a 10 gpm 1 HP submersible pump.  My water had sediment particles in it so I buried 2 one thousand gallon underground tanks in series uphill from my well and pumped my water into them for sedimentation and gravity flow purposes.  Since the tanks are open air ( I have them vented to outside air and water level is controlled by floats which I have set for submersible to pump 500 gallons each refill) the submersible is not pumping against pressure, only gravity.   My setup should extend submersible pump life since it pumps for longer periods and is not subject to multiple starts and stops.
  My 2 stage climatemaster heat pump is set for 6 gpm maximum ( total for both stages ) which I gravity feed to it. When unit calls for water it is delivered quite faithfully day and night as needed.  I have a 1 inch feed pipe to it from the underground tanks and a separate 1 inch pipe for my domestic water supply.  I do have a whole house filter unit  for domestic water supply side and a booster pump to increase the domestic water pressure.  Heat pump water discharge runs downhill via buried discharge hose to my two ponds and keeps them filled and somewhat aerated along with the pond air pump.
  I know my system is somewhat simple and lacking some of the more sophisticated gizmos that may make it more efficient, but it seems to have worked quite satisfactorily and economically to date. 

Hi Rolf, thanks for sharing your interesting geothermal setup! So gravity feed alone for geo! Have you calculated PSI at geo (via how many feet of head - water column). I have found that my geo's efficiency dropped a bit when going from ~70psi to 15psi, but was minimal, flow controlled via dole valve buried outside residence. If your tanks are 30' higher than geo you should be close to 15psi, if less than that I would want to check compressor is running within nameplate amps, or you may have to increase flow due to extremely low pressure.

Nathan

Hi Nathan! I came across this thread a bit ago and it inspired me to install a VFD for my Geo thermal unit. A 3 ton Climate Master. I purchased a PID10 a month ago, and am installing it today. I currently do have a CSV installed, and it has done exactly what I wanted it to do, stop cycles. Great product. Have had it in for 3 years now and no issues at all. When I installed it, my power rates for electric heat were low (3.4 cents per kWh) and it throttled my pump back a little. I was perfectly happy. Now however my electric rates are up (7.2 Cents per kWh) and I am looking to lower pumping costs with out a lot of cost, such as a pump replacement and add on booster pumps etc. I scored the PID10 for $675. The CSV will most likely move over to the other farm and be put into irrigation and livestock watering duties. I will let you know how it goes after my install! Oh by the way my name is Nathan too. I felt the need to register and contribute after reading this thread. Happy New Year!