Jim Brewer wrote:

Paul,
I just got a Northern catalog and they had serveral ceramic heaters

that run

on 12 volts.  One cost $20.00 and was advertised to keep your feet

warm or

defrost your windshield. It had a cigarette plug but could be hard

wired for

greater safety.  Seems like a simple solution for heat.  I think it

weighed

2 lbs.  No plumbing.  Has anyone thought of using this? Cons?

Paul Lamar responded:

500 watts 42 amps at 12 volts.

Not through a cigarette lighter you ain't. :-)

I imagine that the Northern heater is a 300 watt unit.  I cannot imagine

that the

cigarette lighter circuit in most cars is fused at more than 20 or 25

amps.  Since

I *assume* that the Northern folks use the alternator charging voltage

instead of

the battery voltage (to get the numbers higher for the catalog), that

makes a

maximum power available of 25 amps * 13.5 volts =  338 watts.

Then I got smart and went to the Northern online catalog for the *real*

numbers.

:-)  Is this the heater you are talking about, Jim?

http://www.northerntool.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=23041&
prmenbr=6970

200 watts; not exactly a roaring fire.  Keep in mind that a good hair

dryer is

1500 to 1800 watts today.

These two 300 watt heaters look like a better option (50% more heat, and

still

electric):

http://www.northerntool.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=21030&
prmenbr=6970

http://www.northerntool.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=43441&
prmenbr=6970

Of course, the best option seems to be this little 3.9 amp (53 watts)

job:

http://www.northerntool.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=21785&
prmenbr=6970

(but then you're back to plumbing coolant to it).

Russell Kent

Paul,
Yes, the first heater looks like the one in the catalog.  I was not saying
use this to heat your feet.  Defrosting the windshield might be a good
aplication.  I thought some of the other heaters might be able to do both.
Heaters would seem to be better that plumbing . I would "hardwire" all of
them.  I bought a portable air compressor that used the cig-lighter and when
it was plugged in and turned on it promply blew the 15 amp fuse in my Jeep
Grand Cherokee.  What cars and other vehicles need is a better and more
reliable connector than something that was designed to light a cigarette.
Jim Brewer

 
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