We are in the hot humid south so we only deal with cold temps for about 12-14 weeks in the winter and usually no colder than the 50's outside.

We've just heated our work areas with propane and diesel torpedo style heaters because you can warm up a small area with one easily even if there's a lot of air loss due to dust collection and finish booth.

Problem is, our local propane place (an Ace hardware) went belly-up at the end of last winter and now the closest place that does refills is like 12 miles of FRUSTRATING traffic away.

I had worked out a deal with a local Forklift propane supplier to just keep us stocked with full tanks, but they only deal in forklift tanks, and I did not realize that those dispense ONLY liquid propane. The vendor didn't tell us that, he said we just needed an adapter. I haven't inked the deal yet because I cannot find any way of safely using a forklift tank on these portable torpedo heaters safely (they hook up same way a gas grill does).

I'm looking for suggestions here. We're going to use our diesel heaters for now, we have a few that is fine for our very mild temps right now but by Christmas I'm hoping I can find a way of staying stocked up on propane bottles that doesn't involve having to drive across the county.

Im in the northeast and heat my small shop with a Modine ceiling mounted propane heater. I have a 100 gallon tank on the outside of the building and the propane company owns the tank. A quick phone call and the tank gets filled. I'd call around to see if you can switch the heaters out to something more permanent but being in the south...dont know what you have available.

Yeah, we could get a big propane tank refilled. We have natural gas here also. The big sticking point is that all these heaters need to stay portable, so that limits me to portable tanks.

Our shop does lots of different types of cabinetry jobs and over time we rearrange our shop enough that a permanent mounted heater would, within a year or two, end up being in a really odd place to have a heater. Relocating that gas line and electric hookup is not something we care to deal with every couple years lol.

Would you be able to get 33lb tanks instead of the smaller 20lbs ones? I would probably call a propane company and see what they say. If you go through enough propane they may come out and fill 4 or 5 33lbs tanks but thats just a guess.

How do you handle all the water vapor from a ventless torpedo heater? For every gallon of propane you burn, it throws out a gallon of water vapor into the air. That will actually increase drying time of finish.

There's still so much air flow around here that it's completely unnoticed.

We are already a very humid climate, but in winter it really dries out a lot usually, so the vapor coming off the propane just dissipates without causing issues. So most likely, the curing time in the summer at 80 degrees is little different than in winter when we're running propane and getting the temps 70-80.

We used a portable for a couple years. We had a couple of 100lb tanks that local gas service swapped out for us. If you don’t have that option, look for propane company that delivers and have them top off. 100lb tanks are less than $200 each at Home Depot

Not sure about your area, but our propane company brought us out a 500 gallon tank with all of the attachments to fill our forklift/grill/hotwater pressure washer tanks. It pulls liquid propane from the bottom of the tank instead of gas from the top. Been doing it almost 25 years here.

Jamie we've thought about that. Have you ever had anyone screw up and cause any fire hazard issues? Or overfill a tank?

we just open the 80% valve until liquid propane comes out. Then shut it all off. It's not very fast at filling since it's using the pressure of the tank and not an actual pump. If you do it that way, you know there is at least 20% of the tank with room for expansion. We've never had any trouble, but we don't let anyone except managers and maintenance fill them. We just keep a pallet outside with a bunch of filled tanks chained to the fence and if anyone has a forklift die on them, they go swap it with a full one.

While I don't know the layout of your facility, why not hard pipe natural gas thru the shop with quick connects dropped at different locations throughout.
Honestly, I'd lean towards ceiling hung natural gas forced air heaters or ceiling hung radiant if you don't want air movement.

Jim, I hadn't thought of some quick disconnects, I'll keep that idea in mind.

I like the idea of the ceiling mounted heaters, which would work in a couple spots but the main part of the shop just has enough air flow that the ceiling mounted ones would inevitably end up a spot they aren't doing much good. We tend to rearrange our shop every year or two at least a little as we add new equipment, take on special projects, etc.

Many of us rearrange our shops. Why does that affect heater placement? Duct work, electrical, or most anything else can easily be worked around. How does airflow in the main part of the shop affect anything?

What I'm trying to point out is that we have a lot of exhaust in our building between the finish booth, the flatline, and exterior dust collector, we spot-heat our work areas. Our location isn't in a very cold place, the daily low is rarely lower than the 50's so we don't try to heat the entire building, we spot heat.

We could modify our dust collector to return the filtered air back into the building but that won't fix the issues since the finish booth and flatline all pull from the same area.

Move a work station 8 feet in any direction and now your ceiling mounted heater isn't heating that area. But portable propane or diesel heaters take seconds to relocate. As long as you can keep a convenient source of propane, which we have lost.

If you have access to it, I'd go natural gas, without question.
No delivery hassles and burns much cleaner