Testing Solar Pumps

Texas Wellman
Texas Wellman Solar Expert Posts: 153 ✭✭
in Solar Water Pumping #1
I have several solar pumps installed for customers but the other day I had a problem with one. Due to time constraints I was not able to get on the job until late in the day. There was still a little sun available but it was fleeting. I have ran into this problem several times now with installing solar pumps and then not having enough sun to fully vet the systems after they have been installed. It never fails that we will have great sun up until it comes time to run the system but as soon as we finish the cloud/rains will come out!!

I recently purchased (from bison solar) a 110VAC-24VDC converter that I can use with my Honda EU2000i portable genset. I also have a 12V DC plug right off the Honda which really isn't quite enough to test a lot of the pumps I deal with. The 24VDC converter should work well with some of the Lorentz pumps I am using but I have several that take more than 24V to run.

I have a sunpump that uses 3~30volt panels making around 100-110VDC. I have no way to test this pump without the sun. Does anybody make a decent AC/DC converter? Since my Honda is so portable I prefer to use it over a 230V genset so I would need 110VAC to approx. ~100 VDC. I know there will be losses through the gen but 90-100VDC should give me plenty of power.

The genset pushes the Grundfos SQ flex pumps really well and I carry it with me when I test those but they have native 110 VAC built into them.
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  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    #2
    Re: Testing Solar Pumps

    I just finished drilling another livestock well here on the mountain with a Grundfos SQ Flex pump with the control box.

    I don't plan to put the solar panels up until spring but wanted to clean the soap out of the well.

    I have a small Honda EU 2000 generator. Can I use it to run the well (110 VAC) or should I use a larger one? Also, I wanted to tie it into a 1 1/14" ranch pipe pipeline. Will the SQ pump get water to tanks about 1/2 a mile away. The well was drilled to 260 feet and the tanks are 200 feet above the well (say a of total 460 feet)?

    Thanks.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #3
    Re: Testing Solar Pumps

    What model of pump?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Texas Wellman
    Texas Wellman Solar Expert Posts: 153 ✭✭
    #4
    Re: Testing Solar Pumps

    The Honda EU2000i will run all of the Grundfos SQ Flex pumps just fine (all SQF pumps have the same motor, just different pumps). Remember the pump can run on 90-230 VAC or 30-300 VDC, it doesn't even need a control box. The control box is really just an interface. When I test one I bypass the control box and connect straight into the pump.

    You need to size your pump according to the total head on the pump. The depth of the well is not nearly as important as the pumping level. Sometimes the static level and the pumping level are the same but if the well draws down the pumping level will go down and you need to figure that in. For every 50 psi of water use that is approx. 115 ft of head. If you are pumping open ended then you just figure the total head, there is no added head due to pressure. I configure all my solar pumps open ended but they can also do pressure if desired. There is no need to add a 2nd pump/tank etc. if you've got enough pump to do the job.

    For 460' of head you probably need to go with a helical rotor pump that can handle that much head. 460' of head (with no pressure at the end) takes about 200psi at the pump head to get there. I don't have my grundfos charts in front of me but you should be able to pump that easily.

    Water can be moved horizontally a long long way with not much pressure. It's the uphill you've got to worry about. 1.25" pipe is pretty good up to about 20 gpm but it depends on the total distance. The farther the distance the more pressure loss you'll have.
    How much water in a day do you need?
    Mangas wrote: »
    I just finished drilling another livestock well here on the mountain with a Grundfos SQ Flex pump with the control box.

    I don't plan to put the solar panels up until spring but wanted to clean the soap out of the well.

    I have a small Honda EU 2000 generator. Can I use it to run the well (110 VAC) or should I use a larger one? Also, I wanted to tie it into a 1 1/14" ranch pipe pipeline. Will the SQ pump get water to tanks about 1/2 a mile away. The well was drilled to 260 feet and the tanks are 200 feet above the well (say a of total 460 feet)?

    Thanks.
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  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    #5
    Re: Testing Solar Pumps

    Pump is a Grundfos 6 SQF-3.

    I only need a steady 3-5 GPM next to the well to keep the tank full. The pipeline tie in was just in case on a second tank. The second tank is up the mountain 212 feet from the top of the well to the second tank say 1/2 mile. I think the static level of the well is about 170 feet. Don't expect much draw down at low GPM. Looking at the set up well guys thought the pump would fill the second tank upstream ok though slowly.

    Don't remember if the existing pipeline is 1 1/4" or 1 1/2" but it easily handles pumping over a mile away up 250 feet.

    Thanks again.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
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  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    #6
    Re: Testing Solar Pumps

    The two livestock supply lines out of the well head have 1" ball valves so we can open one or both depending on where we are sending the water.

    Was reluctant to set it up that way but the well has a 75 psi pressure relief valve which I assume will pop off if both valves inadvertently get closed while the solar pump is running.

    I figure simpler is better.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
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  • tmarch
    tmarch Solar Expert Posts: 143 ✭✭
    #7
    Re: Testing Solar Pumps
    Mangas wrote: »
    The two livestock supply lines out of the well head have 1" ball valves so we can open one or both depending on where we are sending the water.

    Was reluctant to set it up that way but the well has a 75 psi pressure relief valve which I assume will pop off if both valves inadvertently get closed while the solar pump is running.

    I figure simpler is better.

    I have no problem leaving my pumps run all year and encourage that for my customers. Seems the only ones I have trouble with are those that are shut off for an extended period. 75 psi will tax a marginal pump to the point it could over heat.
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  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    #8
    Re: Testing Solar Pumps
    tmarch wrote: »
    ......75 psi will tax a marginal pump to the point it could over heat.

    It will tax a overloaded motor, that could overheat. 75psi, is nothing unusual. 100' well, and a 40 psi pressure tank, and your pump is looking at 80 psi just there.

    It's very important to match the pump and motor, via mfg's pump curves, to the specific application. But well men seem to
    be eager to sell any pump they have on the truck, regardless of it's suitability.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #9
    Re: Testing Solar Pumps
    But well men seem to be eager to sell any pump they have on the truck, regardless of it's suitability.

    Not "Texas Wellmen". ;)

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Texas Wellman
    Texas Wellman Solar Expert Posts: 153 ✭✭
    #10
    Re: Testing Solar Pumps
    tmarch wrote: »
    I have no problem leaving my pumps run all year and encourage that for my customers. Seems the only ones I have trouble with are those that are shut off for an extended period. 75 psi will tax a marginal pump to the point it could over heat.

    I believe he was talking about leaving the pump accidentally blocked in while it is still running. That is actually a big big problem and the killer of many pumps. What I always do in a situation like yours is drill a little pilot hole through one of the valves so that the water can never fully be shut off. Yes, the 75 psi relief valve is another safety factor but I have seen too many that didn't work quite right and still killed the motor and melted the PVC casing in doing so, ruining the well.
    mike95490 wrote: »
    It will tax a overloaded motor, that could overheat. 75psi, is nothing unusual. 100' well, and a 40 psi pressure tank, and your pump is looking at 80 psi just there.

    It's very important to match the pump and motor, via mfg's pump curves, to the specific application. But well men seem to
    be eager to sell any pump they have on the truck, regardless of it's suitability.

    All the grundfos SQF pumps have the same 3" motor. On a centrifugal pump what kills motors is rapid cycling or dead-heading the pump. When you increase the pressure on a centrifugal pump the amps go down because the work goes down. Helical pumps are positive displacement so they are a different story. There are submersible pumps that can build 1,000 psi of pressure no problem.
    BB. wrote: »
    Not "Texas Wellmen". ;)

    -Bill

    Even when you try to do the right thing and put the right size pump in the customers will complain and say "My neighbor told me" or " why didn't you put a 1-HP 20 gpm pump in my well" when most of the domestic wells around here are perfectly fine with a 1/2 HP 10 GPM pump. They are stuck on HP and GPM even if it is actually too much water and won't last as long. But I try!
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  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    #11
    Re: Testing Solar Pumps

    "Yes, the 75 psi relief valve is another safety factor but I have seen too many that didn't work quite right and still killed the motor and melted the PVC casing in doing so, ruining the well".

    This was the part that really worried me i.e. the pressure relief valve's reliability. Would I be better off removing the well valve for the tank closest to the well and let the excess water run over when opening the main pipeline valve for the remote tank? Or, maybe just wire the valve open.

    As posted the Pump is a Grundfos 6 SQF-3.

    Very good advice Wellman.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
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  • Texas Wellman
    Texas Wellman Solar Expert Posts: 153 ✭✭
    #12
    Re: Testing Solar Pumps

    It's never "you" that will mess up. It's a kid or the wife or the neighbor who will shut the valves and leave the pump running because they didn't know better. Even if you tell them, they will do it.

    You have to make it "foolproof". Drilling the "bypass" through a valve will accomplish that, you just need to make sure that a small split flow can go somewhere and not harm, like overfilling the tank.

    I've even drilled a small weep hole in the drop line which essentially does the same thing but you lose a little water that way. Also I'm not sure how long that configuration would last since (running dead-headed) you're putting the same water back into the well but it's better than doing nothing.
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  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    #13
    Re: Testing Solar Pumps

    We live close to the border. Our infrastructure is frequently vandalized.

    This is why I am so concerned about how my wells are set up.

    Not too worried about over filling tanks as they are not floated. The valves are 1 " ball valves. How big a hole would you drill into the valve body?

    I plan to run the well tomorrow using my Honda EU 2000 generator to clean it out.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
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  • tmarch
    tmarch Solar Expert Posts: 143 ✭✭
    #14
    Re: Testing Solar Pumps
    Mangas wrote: »
    We live close to the border. Our infrastructure is frequently vandalized.

    This is why I am so concerned about how my wells are set up.

    Not too worried about over filling tanks as they are not floated. The valves are 1 " ball valves. How big a hole would you drill into the valve body?

    I plan to run the well tomorrow using my Honda EU 2000 generator to clean it out.
    I probably should have worded my first comment differently, but the idea of leaving one tank on all the time was basically what I was trying to say. Personally I leave the highest tank on and put a float on the lower ones, that way they all stay full or as full as I need. IF your supply line is buried drilling a hole in the pipe in the well would be a better choice than drilling into the underground line or valve IMHO.
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  • tmarch
    tmarch Solar Expert Posts: 143 ✭✭
    #15
    Re: Testing Solar Pumps
    Texas Wellman wrote: »
    I have several solar pumps installed for customers but the other day I had a problem with one. Due to time constraints I was not able to get on the job until late in the day. There was still a little sun available but it was fleeting. I have ran into this problem several times now with installing solar pumps and then not having enough sun to fully vet the systems after they have been installed. It never fails that we will have great sun up until it comes time to run the system but as soon as we finish the cloud/rains will come out!!

    I recently purchased (from bison solar) a 110VAC-24VDC converter that I can use with my Honda EU2000i portable genset. I also have a 12V DC plug right off the Honda which really isn't quite enough to test a lot of the pumps I deal with. The 24VDC converter should work well with some of the Lorentz pumps I am using but I have several that take more than 24V to run.

    I have a sunpump that uses 3~30volt panels making around 100-110VDC. I have no way to test this pump without the sun. Does anybody make a decent AC/DC converter? Since my Honda is so portable I prefer to use it over a 230V genset so I would need 110VAC to approx. ~100 VDC. I know there will be losses through the gen but 90-100VDC should give me plenty of power.

    The genset pushes the Grundfos SQ flex pumps really well and I carry it with me when I test those but they have native 110 VAC built into them.

    Lorentz makes a generator interface, but it's heavy and costly. It will work with the newer 200 controller, but not the older plastic ones.
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  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    #16
    Re: Testing Solar Pumps

    All our pipelines are buried and wells are on generators. We do not use floats on our livestock water storage tanks.

    Ran my trusty Honda EU2000 for a couple of hours to clean soap out of the new well.

    As Wellman said the Grundfos pump ran fine on that little Honda EU2000 without ever leaving its idler speed. Amazing pump technology. The interfaced Grundfos control box is a nice feature. We built and welded on the panel mount a lockable metal boxed housing to secure the control box.

    We prefer semi-automatic systems in the "slow lane". Way out here, trying to operate on automatic can result in lots of problems. Experience talking.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
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  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    #17
    Re: Testing Solar Pumps

    I just had a thought, very simple and will not waste precious water, why not just have a return pipe t return any excess water pumped back to the well of origin. that way the pump can run on solar and probably never run dry...
    just thinking...
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
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  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    #18
    Re: Testing Solar Pumps

    "leave the highest tank on and put a float on the lower ones, that way they all stay full or as full as I need"

    Makes sense. I may do that as our up mountain tanks run over when full while we're pumping with the genset well. I am considering tying the solar well (continuous supply) into our main pipeline and using it for primary supply.

    Thanks
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
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  • tmarch
    tmarch Solar Expert Posts: 143 ✭✭
    #19
    Re: Testing Solar Pumps
    westbranch wrote: »
    I just had a thought, very simple and will not waste precious water, why not just have a return pipe t return any excess water pumped back to the well of origin. that way the pump can run on solar and probably never run dry...
    just thinking...

    Many of these tanks are some distance from the well therefore it's expensive to trench for a return line and basically with an open tank you wouldn't want to return the water with impurities to the well. While water in places takes awhile to return to the underground aquifer it really doesn't go to waste as all kinds of plants and animals benefit from the excess. We aren't talking a lot of water per day as many pumps are sized for each tank or have floats on them.
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  • Texas Wellman
    Texas Wellman Solar Expert Posts: 153 ✭✭
    #20
    Re: Testing Solar Pumps

    Yes, I know about the Lorentz generator interface, and being that I'm a Lorentz dealer I can get it for wholesale prices. But, as stated, it's heavy and costly. I was looking for something perhaps that I was not aware about. It would be nice if somebody made a box that would accept 110VAC and let you select what your output would be...12VDC, 24VDC, 48VDC, 100VDC. I would like to have about 600 watts to work with, which is the equivalent of about 3 200-watt panels. Since I deal with so many systems it would be nice to have one tester box.
    tmarch wrote: »
    Lorentz makes a generator interface, but it's heavy and costly. It will work with the newer 200 controller, but not the older plastic ones.
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #21
    Re: Testing Solar Pumps
    Texas Wellman wrote: »
    Yes, I know about the Lorentz generator interface, and being that I'm a Lorentz dealer I can get it for wholesale prices. But, as stated, it's heavy and costly. I was looking for something perhaps that I was not aware about. It would be nice if somebody made a box that would accept 110VAC and let you select what your output would be...12VDC, 24VDC, 48VDC, 100VDC. I would like to have about 600 watts to work with, which is the equivalent of about 3 200-watt panels. Since I deal with so many systems it would be nice to have one tester box.
    Here is a type I bought a few years ago after I saw one being used at the Inverter Service center. It's what they use on the bench while repairing Inverters instead of batteries. I think the go up to 100 V / 50 Amps.

    They are great to EQ one battery at any voltage or a bank, I use mine everyday.

    http://www.mastechpowersupply.com/variable-power-supply/switching-power-supply/cat_7.html

    You also need a set leads they are in the " Sale Items " I know a weird place to have them.
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  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    #22
    Re: Testing Solar Pumps

    This might sound weird, but what about a small MIG or TIG welder, 110 in and you can vary the output level?
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
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  • Texas Wellman
    Texas Wellman Solar Expert Posts: 153 ✭✭
    #23
    Re: Testing Solar Pumps

    This is exactly what I was looking for, thank you!!
    Blackcherry04 wrote: »
    Here is a type I bought a few years ago after I saw one being used at the Inverter Service center. It's what they use on the bench while repairing Inverters instead of batteries. I think the go up to 100 V / 50 Amps.

    They are great to EQ one battery at any voltage or a bank, I use mine everyday.

    http://www.mastechpowersupply.com/variable-power-supply/switching-power-supply/cat_7.html

    You also need a set leads they are in the " Sale Items " I know a weird place to have them.
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #24
    Re: Testing Solar Pumps
    Texas Wellman wrote: »
    This is exactly what I was looking for, thank you!!
    Your Welcome. Make sure you get the " EX" model as they hold the settings and won't drift. Example if you want 100 Volt / 10 Amp, you'd a HY10010EX . I don't know what you want as far as Amps.

    http://www.mastechpowersupply.com/dc-power-supply/switching-power-supply/volteq-power-supply-hy10010ex-100v-10a-over-voltage-over-current-protection/prod_111.html
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  • pechan
    pechan Solar Expert Posts: 92 ✭✭
    #25
    Re: Testing Solar Pumps
    Texas Wellman wrote: »
    It's never "you" that will mess up. It's a kid or the wife or the neighbor who will shut the valves and leave the pump running because they didn't know better. Even if you tell them, they will do it.

    You have to make it "foolproof". Drilling the "bypass" through a valve will accomplish that, you just need to make sure that a small split flow can go somewhere and not harm, like overfilling the tank.

    I've even drilled a small weep hole in the drop line which essentially does the same thing but you lose a little water that way. Also I'm not sure how long that configuration would last since (running dead-headed) you're putting the same water back into the well but it's better than doing nothing.


    How about buy a 3 way valve?
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