The awful truth (Grundfos SQF) [RE-wrenches]

Larry Brown, Sunmountain sunmountain at netstep.net
Sun Feb 12 07:24:57 PST 2006


Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Unlimited International Calls to Certain Counties with
Packet8. Our International VoIP Plans offer subscribers a
easier way to save on overseas calls. 1-877-868-1135
http://click.topica.com/caaer6Ibz8Qcsbz9JC9a/ TMONE
-------------------------------------------------------------------

Jim,

Please slow down on sending me the "doom & gloom" e-mails.  You are over
loading my inbox and my head.

Thanks,
Larry
----- Original Message -----
From: "Matt Tritt" <solarone at charter.net>
To: <RE-wrenches at topica.com>
Sent: Saturday, February 11, 2006 1:55 PM
Subject: Re: The awful truth (Grundfos SQF) [RE-wrenches]


Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Is your computer freezing up or slowing down?
Repair corrupt files and harmful errors - protect your PC
Take a 2-minute PC health check-up at no charge!
http://click.topica.com/caaerelbz8Qcsbz9Lpka/PC Powerscan
-------------------------------------------------------------------

Windy,

A good observation, but it turned out to be a very different problem,
and once again reminds me to verify customer's conclusions before I go
shooting my mouth off! I also have to say that I fixed the problem (time
will tell) thanks to a suggestion from somebody @ Grundfos who, no
doubt, has encountered this situation before.

The PV modules that were supposed to be 6/12 volt output turn out to be
12/24 (as I bloody-well should have known!) and, even though the pump
spec's claim that it should work fine in a 48 volt configuration, the
Grundfos tech suggested re-wiring it to 96 volts. Presto! The Wattage
went from 290 - 320 up to 380 - 390 at operating cell temp, the ramp-up
takes way less time and the flow increased from 5 GPM to 6. This is
pretty graphic proof of the importance of using higher voltages with the
SQ Flex than what the factory manual calls for (30 to 300 volts), and
gets me wondering if they should change their performance claims.

I've never had this particular kind of problem with the Lorentz pumps! ;-)

Matt



Windy Dankoff wrote:
>
> Matt,
>
> Is the water warmer than normal ground temperature? That causes the
> rubber stator (in the helical rotor pump end) to expand a bit and
> tighten against the rotor. Makes it harder to start, especially under
> low-power conditions of low light or a minimal PV array relative to
> the load.
>
> In that case, it would be only a temporary condition and the factory
> would find no flaw.
>
> Windy

>

Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Get your VoIP on with Packet8's Videophone.
Crystal clear images of your loved ones. Free Month.
30 day money back guarantee. 1-877-868-1135
http://click.topica.com/caaer6Ebz8Qcsbz9Lpkf/ TMONE
-------------------------------------------------------------------

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://lists.topica.com/lists/RE-wrenches/read

List rules & how to change your email address:
www.mrsharkey.com/wrenches/etiquette.php

Check out participant bios: www.mrsharkey.com/wrenches/

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com

Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Is your computer freezing up or slowing down?
Repair corrupt files and harmful errors - protect your PC
Take a 2-minute PC health check-up at no charge!
http://click.topica.com/caaerelbz8Qcsbz9JC9f/PC Powerscan
-------------------------------------------------------------------

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://lists.topica.com/lists/RE-wrenches/read

List rules & how to change your email address: www.mrsharkey.com/wrenches/etiquette.php

Check out participant bios: www.mrsharkey.com/wrenches/

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com
--^----------------------------------------------------------------
This email was sent to: michael.welch at homepower.com

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9.bWljaGFl
Or send an email to: RE-wrenches-unsubscribe at topica.com

For Topica's complete suite of email marketing solutions visit:
http://www.topica.com/?p=TEXFOOTER
--^----------------------------------------------------------------









More information about the RE-wrenches mailing list