There sure are a lot of neat posts on this subject here.
A couple of them have hinted at the condensation problem of unvented
fossil fuel heaters, but it sounds like many of you have missed that
point!!!!!
You get LOTS of water!!!!! If you are trying to keep your machine
tools from rusting in such an environment, forget it!!!! You are simply
shooting yourself in the foot.
I occasionally work long days in a guy's garage that has an overhead
gas furnace. It gets up to 80 degrees 7 feet off the floor, but the
floor can be 10 or 15 degree at times. So, personally, I use gas wall
furnaces of the counterflow type. They are vented, suck air in at the
top and blow it out at the bottom where it has a chance to heat the
floor. They mount between 2 wall studs that are on standard 16 inch
centers. If you get the direct vent model (as opposed to the top vent
or chimney models), it vents out through the wall and uses outside air
for combustion.
As I get older, my biggest comfort problem is my lower legs, so
that is where I want the heat.

If what you really need is to keep the machine tools from rusting, you
only need to keep those immediate areas from condensing water out of the
air. I suggest that you cover each tool loosely with a plastic tarp and
thoughtfully (safely) place a single light bulb under each tarp. It may
only take 60 watts or so. All you need to do is to keep the tool a few
degrees abouve the room ambient temperature to avoid the condensation.

Waiting for new shop furnace to arrive as we speak,
Pete Stanaitis (western Wisconsin)
----------------------------------------------------
Taunt wrote:

It's getting a little chilli in the garage and need to buy a heater.

Pros and cons?

Propane?
Kerosene?
Oil filled electric?

TIA, Jack