Low voltage Air Conditioning [RE-wrenches]

Mon Apr 21 12:15:26 PDT 2008

	This seems like a good way to do it. I would look closer at the
BTU requirements. 20,000 Btu is a 1 1/2 tons of AC. It would feel like a
meet locker in most sleepers and sound like a turbine. Unless the out
side air temp is 160 to 180 degrees. Most sleepers are insulated for
sound reasons and are sealed from air leakage. By my calcs the heat gain
in the Nevada desert would be 1/4 ton or 3000 BTU (very Conservative).
Because the truck has AC you would be able to drop this more if the new
AC unit is expected to maintain the temp after the truck is turned off.
If you want the new AC unit to pull down the temp say 100 degrees to 70
degrees without the use of the trucks AC a 3000 BTU unit would be fine
but over kill once the design temp has been meet.
	From my driving days I would rather use the truck and AC unit to
pull it down then turn the truck off and let the unit maintain the temp.
This would mean less airflow so less sound for the driver to get use to.

	I am not up on DC units but I think small camper roof top units
are DC and would be more in line on the power consumption side.   

Chris Meier

Product Manager

UniRac, Inc.

1411 Broadway Blvd. NE

Albuquerque, NM   87102-1545

Ph:  505-242-6411 

Fx:  505-242-6412

Email:  chrism at unirac.com 

Web:   http://www.unirac.com

This message contains confidential and privileged information, which is
intended for the individual(s) to whom it is addressed.  It should not
be reviewed, retransmitted, disseminated, or otherwise used by a
person(s) or entities other than the intended recipient.  If you
received this message in error, please contact the sender and delete the
material from your computer system(s).

-----Original Message-----
From: Travis Creswell [mailto:tcreswell at ozarkenergyservices.com] 
Sent: Monday, April 21, 2008 11:18 AM
To: RE-wrenches at topica.com
Subject: RE: Low voltage Air Conditioning [RE-wrenches]

Hello Larry,

You mention a "small diesel generator".  Are you talking about an
Auxiliary
Power Unit or a generator?  APU's are becoming really popular on trucks
from
what I've seen.  They are generators and air conditioners so they take
care
of two birds with one stone.  Here is an example of one.
http://www.rigapu.com/index.php  I have no affiliation with them, it's
just
the first hit on Google (who I also have no affiliation with).  They
"comply
with strict idling laws" so I would assume they are allowed.  I'm sure
it's
pricey but so are all those batteries.  By the way, where are you
planning
to put 18kWh worth of batteries?  That's ~8 L-16's or ~14 T105's by my
math.
Plus that weight results in that much less freight he can carry which
might
be a deal breaker all by itself.

According the specs; 20,000 BTU of cooling capacity, 6kW generator and
60
amps of DC output, .3 gallons per hour at full load.   Hmnn...these
could be
a solution for off gridders that wanted/had to have air conditioning.
(No
comments needed from the efficiency peanut gallery, please)

Best,
Travis Creswell
Ozark Energy Services

-----Original Message-----
From: Larry Crutcher, Starlight Solar [mailto:larry at starlightsolar.com] 
Sent: Monday, April 21, 2008 11:27 AM
To: RE-wrenches at topica.com
Subject: Re: Low voltage Air Conditioning [RE-wrenches]

Wrenches,

I did not get a response to my post from last week. I know most of you
do
not work with battery based systems but is there anyone here that can
offer
some experiential advice about low voltage air conditioning? 

Thanks again,
Larry Crutcher
  ----- Original Message ----- 
  From: Larry Crutcher, Starlight Solar 
  To: RE-wrenches at topica.com 
  Sent: Thursday, April 17, 2008 11:30 AM
  Subject: Low voltage Air Conditioning [RE-wrenches]

  Does anyone have experience with DC air conditioning equipment? I have
a 
  customer with a semi truck and wants a roof air for the sleeper.  Many

  truck stops now forbid engine idling for more than 5 minutes so they
can 
  not use the cab air. 

  A small diesel generator is one solution but the trucker is not sure
if 
  some truck stops may forbid that as well. Since the truck engine is
only 
  off for 10 hours or so, it looks like 18kWhr of battery @ 50% DOD
will 
  operate the A/C load until the engine starts again. 

  Some customers in Mexico are running mini-splits successfully but I 
  don't want to add the complexity of an inverter if there is a low 
  voltage DC solution.

[Non-text portions of this message have been removed]

No virus found in this outgoing message.
Checked by AVG. 
Version: 7.5.524 / Virus Database: 269.23.2/1389 - Release Date:
4/21/2008
8:34 AM

- - - -
Hosted by Home Power magazine

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/

Moderator: michael.welch at homepower.com

- - - -
Hosted by Home Power magazine

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/

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

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
--^----------------------------------------------------------------