Garage/Shop furnace?

James Terrio

Well-Known Member
Winter time is coming fast and I have a ton of work to do. I've been looking at some "portable" wall furnaces at Menards... the one I think I want needs no venting, and can run off propane or NG, is rated for either 20k or 30k BTU (I forget exactly) and costs about $150. They claim it's powerful enough for the square-footage I have.

I don't think I can afford to run natural gas to the shop this year so I was thinking that might get me by for a season? The proper shop furnace I really want is close to $500 and who knows what having the gas line put in will cost :(

I have a dedicated 50-amp circuit running out to the shop and plenty of 15- and 20-amp outlets but I think an electric heater would be awful expensive to run. I used a friend's kerosene heater last year and it warmed up the place nicely but I was spending $20/week or more on fuel, using it sparingly. Would the propane be cheaper to run?

I really don't know, if it's gonna cost me a ton to run I might be better off biting the bullet and going for a proper furnace.

My shop is 16'x32'. I used about 8 cans of Great Stuff to seal up all the cracks before we put the insulation in last year. The walls and roof have R11 fiberglass insulation and vapor barrier. The garage door has a 2" layer of solid pink foam on it but I think I need to put some fiberglass or something over it, it still lets a lot of cold through.

It doesn't have to be 72 degrees but I'd like to be able to get it up to at least 50 so I can move my fingers while working!

Thanks for any tips or ideas. I'm sure some of you have been in a similar situation.
 
Last edited:
Hi James,
I owned one of those blue flame vent-less propane wall heaters, and would advise against it! It made all of my machines sweat with condensation. I would go with a vented heater system.
The overhead infrared propane heaters are vented and heat objects instead of air, several of my friends have them in there garage and they work great! I use a wood burner and have to warm my shop every morning. Hope this helps a little !
Sincerely,
Sampson Knifeworks
 
I use one of these

http://www.mrheater.com/product.aspx?catid=42&id=23
MH24t.jpg


It's pretty good right now, but when we are in the middle of winter, it takes time to go from really cold to tolerable.

I have noticed that unless i keep the room vented with a door or window cracked, I start to sweat, and later I'm red in the face, like a wind burn or an alcoholic glow of good cheer.
(Carbon Monoxide poisoning)
Since I'm more stock removal than forging, I don't have a CO detector.

my point...
use a CO detector.
vent ( counter intuitive to let in that cold air we are trying to keep out

Consider installing a permanent separate furnace in your shop area.
With people installing super high efficiency units, the removed furnaces can still be quite good for the shop area
Efficiency has to be better with those than with the portable units I'm using.
Those direct vented units can be put just about anywhere and piped out the wall.


my dream is a heated floor, but that involves ripping, digging prepping and pouring a new floor.....
 
Last edited:
Hi James,
I owned one of those blue flame vent-less propane wall heaters, and would advise against it! It made all of my machines sweat with condensation. I would go with a vented heater system.
The overhead infrared propane heaters are vented and heat objects instead of air, several of my friends have them in there garage and they work great! I use a wood burner and have to warm my shop every morning. Hope this helps a little !
Sincerely,
Sampson Knifeworks

I have some experience with those tube type heaters from past workplaces.

It's good that they warm up people and machines directly - and are vented outside too.
My lathe bearings are tight in the extreme cold and she needs to warm up first.

They work, but they are very directional.
burning hot underneath and dead cold just a few feet to either side of their zone.
Either they should be mounted high enough to have a proper spread, or there should be more of them installed
$$$
Try to visit actual shops with different setups before you do something.
 
...Consider installing a permanent separate furnace in your shop area.

Oh yeah, I know I will need to do that at some point. Just not sure I can afford it this year and trying to sneak through this winter without laying out too much cash. But if I gotta fill a tank every few days I may as well try to do it right the first time... still open to ideas tho!

... my dream is a heated floor, but that involves ripping, digging prepping and pouring a new floor.....
Yeah those are mighty nice. If I ever start over and build my dream shop from the ground up, I think that's the way to go.

I'm a stock removal guy too but with any kind of gas heater I will need a CO detector in the shop, thanks for reminding me.
 
I would say move to mississippi, but anyone who hasn't lived here their whole life would despise the weather patterns, 30 degree temp swings are not outside of possibility.
 
James, I'm kind of in the same boat. I think the best solution for me would be to eventually put a wood burning stove in. I can't afford it right now, but maybe I'll get one by next winter. I also like the idea of having something that is off the grid in case of a power outage. I have some propane heaters but, as it's been mentioned, you need to vent the shop to use them, so it kind of defeats the purpose. I get a little worried about the open flames too.
 
Mark, I've thought about a wood-burner or pellet stove too and you raise good points, especially having heat "off the grid". You can buy a whole lot of pellets or cordwood in my neck of the woods for fairly cheap, maybe even cheaper than natural gas. I imagine a guy would have to talk to the local building inspector and his insurance agent first, but it may be an option.

I'm swamped with holiday stuff, orders and moving chores but maybe weekend after next I'll be able to really sit down and do some research. MAYBE I should have started planning this about 3 months ago :what!:
 
Pellet stoves require electricity and I have heard that the hopper motors in them need replacing frequently. If you buy one of the new wood burners before the end of year you can qualify for the energy tax credit and get thirty percent off the stove and installation on this years tax return. Certain stoves do not qualify though, do the research.
Stay warm!
Sincerely,
Sampson Knifeworks
 
I live in a four season climate . My shop is 13' X 26' X10' high. I use an air conditioner in the summer and now an electric heater. I bought a "Patron" a couple of years ago that was the real cats whiskers to begin with but has become useless. It cost about $450. I am now back to one of those "cubes" that here in Canada run around $60. These all run on 220 voltage.I used one similar years ago in a far colder climate in a space about the same size. It's doing a super job!!! My shop is half of a double garage that has a seperating wall with the best of insulation sides and in the ceiling. We have had a cold snap and it was replace or no work for Frank. The outside day temperature is 0 degrees.
 
Light the Forge!! :)

I'm a stock removal guy. Maybe I could fire up the Paragon kiln and leave the door open? OK not a real good idea.

Hmmmm maybe this is a good reason to buy an anvil and build a forge?!? :D I've always intended to get into forging sooner or later...
 
I'm a stock removal guy. Maybe I could fire up the Paragon kiln and leave the door open? OK not a real good idea.

Hmmmm maybe this is a good reason to buy an anvil and build a forge?!? :D I've always intended to get into forging sooner or later...

Most forges will cause the same venting issues as a propane heater, just so you are aware. Not that they can't warm your shop up, but running one indoors creates it's own risks and issues. Swinging a 3 or 4 lb hammer will warm you up a bit all by itself, though, compared to standing at a grinder.
 
I have a 16' x 32' shop that is split in half, one side for forging that I don't worry about heating(major BTU's) and the other side with a wooden floor. The whole shop is well insulated. Just after I built the shop I went through the same dilemma. After much research I settled on an edenpure heater. I paid about $350 for it, it is an electric heater, but with no exposed elements. This heats my shop to 70f easily, (like Frank I live through 4 seasons, although it doesn't get quite as cold) for about $1 a day. I don't know how well this would work with a concrete floor. This will be the third winter and I am happy.
 
I've seen the EdenPure heaters on TV but I'm always leery of infomercials. Your experience sounds interesting indeed. $350 would be less than the gas furnaces I've looked at and I wouldn't have to pay to have gas-lines run.

I decided propane is out of the question for me, just too expensive. For now I picked up a small electric "quartz" heater ($40) and it does help quite a bit within a small area. It's only gotten down to about 20 degrees so far here, we'll see how it goes when it actually starts getting cold. ;)
 
It takes @ 96,000 btu of propane burning non stop for 1 hour to burn a gallon of propane. A 100 lb. cylinder hooked to a 30,000 btu ventless heater will run approx. 1 week in a well insulated house before needing refilled. Most houses using stricktly a ventless heater in Missouri will only use @ 330-500 gallons of propane a winter.

I have a ventless blue flame hooked to my house tank and inside my 10x16 finishing room in my shop. Yes, I do have some sweating and I do have to be careful not to spray any type of wd-40 or similar chemicals while it is running, but I also get sweating problems without heat at certain times of the year. But, I'm off the grid with the ventless heater.

I recommend them as long as people no their limitations. If you spray wd-40 in the shop you will smell the fumes when they go through the heater and you will get a headache so beware. But, I've used everything from electric space heaters, kerosene heaters, and ventless propane heater and I prefer the ventless in my shop. Easy to clean and maintain, can be easily shut down and the gas turned off when I leave, and will heat my finishing room from 0 degrees to 80 degrees in @ an hour or less. Plus when I'm done for the day I just turn it off, turn off the gas valve underneath, and I don't have to worry about anything until the next time I get out to the shop.

Good Luck and stay warm!
 
Back
Top