[RE-wrenches] Lorentz Sub Pump

Wed Apr 21 23:07:07 PDT 2010

We've found the SQ Flex to be install-and-forget for many years. Lots of installations with never a call from customers. Except that we have had 3 apparent CU-200 failures in the last few months. And Grundfos has been very hard to deal with on the warranty. We've had to replace the unit on our dime, send it back, and wait 2-3 months for Grundfos to decide it was a warranty issue. Then they credit our supplier who credits us. Another installer we know has mentioned this has been a problem lately. Anyone else seeing this?

Bruce Erickson
Mendocino Solar Service
PO Box 1252
Mendocino, CA 95460
707-937-1701

On Apr 21, 2010, at 3:47 PM, Dana wrote:

> We had about a 50% failure rate with Lorentz pumps and controllers and stopped installing them, as Allan said “back when.”
>  
> The Grundfos SQ Flex pump has been our choice and not even 1 bad one yet and same pump for DC and AC. Pretty bomber Pump.
>  
> I would be glad to hear that they got it all sorted out.
>  
> Thanks,  Dana Orzel
>  
> Great Solar Works, Inc
> web - www.solarwork.com
> E - dana at solarwork.com
> V - 970.626.5253
> F - 970.626.4140
> C - 970.209.4076
>  
> "We have been slow to give up on the myth of the Earth's generosity.
> Rather grandly, we have overdrawn our accounts."
> Barbara Kingsolver - Water is life.
>  
> From: re-wrenches-bounces at lists.re-wrenches.org [mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Allan Sindelar
> Sent: Wednesday, April 21, 2010 4:41 PM
> To: RE-wrenches
> Subject: Re: [RE-wrenches] Lorentz Sub Pump
>  
> We were burned pretty well by the period of bad Lorentzes and vowed never again. Given the long time and close relationship between Windy and myself, that wasn't decided lightly. Given Chris' and Jeff's posts, I'm willing to cautiously reconsider.
> 
> Dave, you need to find out the vintage of the pump you're dealing with. Our bad ones were around 2003-5, then we stopped using them.
> 
> I think the problem wasn't with the stator, as I never saw motor failure. Rather, either the rubber compound or the manufacturing tolerances/coefficient of expansion on the helical rotor surround were off, causing failure. Also, a few controllers failed.
> 
> I'm surprised I've not yet seen a problem with the SQFlex yet.
> Allan
> 
> Allan Sindelar
> Allan at positiveenergysolar.com
> NABCEP Certified Photovoltaic Installer
> EE98J Journeyman Electrician
> Positive Energy, Inc.
> 3201 Calle Marie
> Santa Fe, New Mexico 87507
> 505 424-1112
> www.positiveenergysolar.com
> 
> 
> Chris Worcester wrote:
> Hi Dave,
> We have lots of the Lorentz systems in the field operating either from PV direct, battery based or AC. I like them, and find them very reliable. You need to check that the pump is matched to the well’s statistics. Did they install the low water sensor with the pump?
>  
> Sincerely,
> 
> Chris Worcester
> Solar Wind Works
> NABCEP Certified PV Installer
> Phone: 530-582-4503
> Fax: 530-582-4603
> www.solarwindworks.com
> chris at solarwindworks.com
> "Proven Energy Solutions"
>  
> From: re-wrenches-bounces at lists.re-wrenches.org [mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Dave Palumbo
> Sent: Monday, April 19, 2010 12:41 PM
> To: 'Wrench List'
> Subject: Re: [RE-wrenches] Lorentz Sub Pump
>  
> Wrenchers,
>  
> Looking for advice on the following pump. Lorentz PS600-HR04H-1-48B with power pack option and controller.  
> I will be doing an off-grid system for a homeowner who already who had purchased this pump, in fact it is down the well already, although not working, or even  wired to anything yet. The dealer who sold her this pump is no longer working this job. That dealer did not install anything else. So, we have a clean slate except for this pump.
>  
> Homeowner is willing to go with another pump if I’m not satisfied of this pumps quality, suitability for her home and reliability.
>  
> I have never used a Lorentz pump before. I do recall some mixed reviews over the years on this list on Lorentz pumps.
> Typically for a home like this (modest water needs) I would install a Grundfos SQ AC pump with a standard pressure tank and run it off the inverter.
>  
> We could do a 48 volt battery bank for this home, so we could do the Lorentz pump. This pump is designed to be powered with 48VDC nominal correct?
>  
> Is it a reliable pump?
> Or will it be more trouble than the AC Grundfos?
>  
> Thanks,
> Dave
>  
> David Palumbo, NABCEP Certified PV Installer
> Independent Power LLC
> Offices in Lamoille and the Champlain Valley
> 802.888.7194
> www.independentpowerllc.com
>  
>  
> 
> 
>  
> _______________________________________________
> List sponsored by Home Power magazine
>  
> List Address: RE-wrenches at lists.re-wrenches.org
>  
> Options & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>  
> List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>  
> List rules & etiquette:
> www.re-wrenches.org/etiquette.htm
>  
> Check out participant bios:
> www.members.re-wrenches.org
>  
>   
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 9.0.814 / Virus Database: 271.1.1/2826 - Release Date: 04/21/10 05:09:00
> 
> _______________________________________________
> List sponsored by Home Power magazine
> 
> List Address: RE-wrenches at lists.re-wrenches.org
> 
> Options & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
> 
> List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
> 
> List rules & etiquette:
> www.re-wrenches.org/etiquette.htm
> 
> Check out participant bios:
> www.members.re-wrenches.org
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20100421/8b677830/attachment-0003.html>