Expensive but not reliable helical rotor pumps.

raysubtropicalraysubtropical Registered Users Posts: 14 ✭✭
I operate three solar pump wells off grid for 13.5 years and use a generator to makeup for overcast days and high watering demand. I have had great results with early versions of the 11SQF-2 and 6 SQF-3 pumps (8.5 yrs MTBF) made in denmark. Two recent wells were drilled and I of course went and purchased two 11SQF-2's, both were made in mexico. The two solar pumps stopped pumping about 3 months apart. And just a couple of months out of a "2 year warrantee period". I asked a local grundfos rep to look at my pump but there response was "it was out of warrantee". So I proceeded to find out the cause of failure. I removed the rotor jacket and tried turning the rotor by hand but stops against a hard metallic object. So I know it was not worn out. My guess without cutting open the motor ....is that one of the magnets came loose inside the motor housing. My concern is that both pumps failed early without warning. Both may have quality issues. This discussion may open up a big can of worms but id like to hear what others are experiencing.       


  • EstragonEstragon Registered Users Posts: 4,478 ✭✭✭✭✭
    Regardless of where it's made, it wouldn't shock me to learn corners are being cut on an otherwise well respected brand. What does concern me is the apparent lack of rep interest and deficient feedback to decisionmakers.

    It's one thing to minimize production costs, and maximize profits. That's what management gets paid to do. Doing it right, IMHO, means finding the problems that inevitably happen in the process, and fixing them.

    It's an entirely different thing to coast on a brand name, put no priority on feedback from customers, and treat the brand as a wasting asset.
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • mcgivormcgivor Solar Expert Posts: 3,427 ✭✭✭✭✭
    edited June 2018 #3
    Sometimes manufacturers change materials, to reduce toxic chemicals for example, water based adhesives, lead free solder, which often do not perform as well, thus creating a fundemental flaw in an otherwise good product. The support the manufacturer provides to remedy such issues is in direct proportion to the negative advertising which could result, especially these days where broadcast  over social media spreads lIke a virus. Dealing directly with the head office rather than a distributor can often be more rewarding in terms of service. My first well pump failed due to a thermo fuse issue built into the windings, dealer said sorry out of warranty, by 3 months, contacted Jiadi directly, they sent a replacement motor free of charge, including shipping, along with apologies. That's what I call customer support.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.  
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  • EstragonEstragon Registered Users Posts: 4,478 ✭✭✭✭✭
    Good point. It could be the local rep, not the manufacturer.
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • raysubtropicalraysubtropical Registered Users Posts: 14 ✭✭
    Sorry I'm not familiar with the "Jadi" brand...sounds like an indian start up brand? Maybe gloss over your model number and your well's dynamic head please. At least you found their nerve ending and started to poke.
    I don't think the pump quality and longevity has anything to do with meeting environmental and health regulations in mexico. I purposely bought my tacoma (made in tijuana, Mx. vs Oakland) to get a petroleum base paint vs a water base. And yes the paint is doing fine.  

    I'm really looking to dump grundfos (so far 2 have failed pre-maturely and 1 that never pumped a drop). This time I plan to get the word out and cause some retribution. Two recent pump failures puts our operation at financial risk. This forum may also provide (-) feedback to distributors and corporate that monitor this site and may get their ear. 
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