I know many of you have catalytic heaters. While we all make our own choices I don't believe catalytic heaters are safe. While the vented catalytic heaters may be safer, they still don't provide outside combustion air, and have a hot surface that poses fire risks.
There are alternatives. Here is a roundup:
1)
The Dickinson Newport propane fireplace. 7500 and 9700 BTU/h output versions available, $700 street price for the 7500 BTU/h including vents. Vents vertically using tri-wall pipe. Outside combustion air is drawn from the concentric area. Requires no electric power though there is
12v blower for air circulation that can be used if desired. Cearance to combustibles - top 18", other 5 surfaces 2", vent pipe 2"
2)
Propex heater. Popular with the Westfalia crowd because of the installation flexibility it provides. Imported from the U.K. This is a ducted heater that mounts inside. 1" clearance to combustibles. Unlike Atwood and Suburban heaters, which have rigid vents limiting the installation possibilities, combustion air and exhaust are vented outside through 1" flexible tubing. 6000 and 9600 BTU/h (output) versions are available, drawing 1.4A and 1.9A respectively. $800 street for either size from U.S. dealers.
3)
Atwood Everest Star 8012. This is an unducted furnace with a smaller, lower current blower than the duct versions. Zero clearance, direct vent. Draws 1.8A. 9100 BTU/h output. $500 street.
As a point of comparison the vented catalytic heaters often advocated are available in 3000 BTU/h and 5000 BTU/h sizes. Each draws 0.5A.
$500 street. For further comparison the (unvented) Olympian Wave 8 is an 8000 BTU heater, $330 street, no electricity required.
Going the other way the larger furnaces from Atwood and Suburban typically have a 26,000 BTU/h output and draw about 10 amps.