Garage Heater Recommendations

[c30]

I remember running a kerosene torpedo heater in a barn shop many years ago.
Those things will kill you in an enclosed space and I never want to smell that smell again.
What I've done since is to use a regular updraft furnace. Typically, just sitting on the floor with a filter on the return. Put a plenum on top of it so you can divert the supply air to wherever you need it. Vent it properly.
Natural gas or propane. Mount a thermostat wherever.
I have a friend in the hvac business. He often changes out furnaces that are older. Usually, he just scraps them.
Find a used 50 to 60000 btu furnace for free or cheap. The older ones have less BS in the control system and are more reliable.
It's 65 degrees in my garage right now and 25 degrees outside. I'm good.
Mine has electronic spark ignition, no pilot light.
Just remember to warm up the shop real good and turn off the furnace if you are doing any spray painting.