Battery chargers do make good power supplies unless designed for that extra function. Power supplies have filtered and regulated outputs to actually support devices or equipment

Dennis

Sent from my Windows Phone
________________________________
From: David Beierl
Sent: 12/23/2011 12:37 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Front Heater wiring *REVISITED*

At 11:49 AM 12/23/2011, Dennis Haynes wrote:
>What was the random power source? Maybe it did not have the capacity
>to run the motor. You need power,volts and amps.

Good point.  If your source isn't the vehicle battery it has to be
able to supply several amps at twelve volts to run the blower at all,
and twelve or more to run it at full speed.  Typically the only
easily available source that will do this will be a lead-acid battery
of some sort or maybe a ten-amp battery charger (not a desirable
source without a battery hooked to it).  One of those jump-start
packs would be fine.

Yrs,
d