Choosing a shop heater

  • Advertise with us

« back to Focus on the Workspace forum

Forum topic by Ben posted 01-10-2016 08:03 PM 1601 views 0 times favorited 20 replies Add to Favorites Watch
View Ben's profile


491 posts in 3915 days

01-10-2016 08:03 PM

Hey all,

I’ll soon be insulating my 20’x20’ shop with 3” rigid foam panels (about R20) in walls and ceiling.

I am thinking of a ceiling hung Modine style propane heater because I don’t want to sacrifice floor space, and because they are readily available used. Only downside I can see is that propane is pricey.

But, what about the combustion chamber on these? Aren’t they essentially open? Even with dust collection is there a risk of fine dust particles ignited and causing a fire?

My shop is in my detached 2 car garage, so a lot of other options are impractical.
I could theoretically do an oil fired furnace, but they seem to take up a lot of space.

Thanks for any advice.

20 replies so far

View Fred Hargis's profile

Fred Hargis

6928 posts in 3551 days

#1 posted 01-10-2016 08:41 PM

If you buy a used one it will likely draw room air in for combustion, so yes it’s basically an open chamber. Newer ones can be had with direct vent (outside air for combustion and a sealed chamber) and is what I have in my shop. This one is a Sterling Garage Guy, but it’s pretty much the same as a Modine. Even so, I think the chances of fire are very slim even with an open chamber; although spraying lacquer in the shop would be highly discouraged. More likely, seems to me, is the chance of dust buildup on some electrical component causing a malfunction in the furnace. that’s the main reason I bought the direct vent model. Sterling claims it increase efficiency as well, but I doubt it would be enough to measure without laboratory instruments. As for cost, this year the price of LP is pretty low (I paid 99¢/gallon) but of course last year was a completely different story. To heat my 24×32x8 shop (R19 walls and R40 ceiling) I burned 150 gallons last year, heating to 65ºwhen I’m in there (most days for 8 hours) and 55º at night. Still cheaper than electric, except for the initial installation.

-- Our village hasn't lost it's idiot, he was elected to congress.

View Bill White's profile

Bill White

5349 posts in 5018 days

#2 posted 01-10-2016 08:50 PM

Look at the oil filled radiator style elec. heaters. That’s what I use. No flame, fumes, danger from goofy stuff.
Might not be the best from an economic standard, but I sure feel safe with them.

-- [email protected]

View timbertailor's profile


1594 posts in 2482 days

#3 posted 01-10-2016 09:35 PM

One thing most do not consider is that propane creates a very humid environment when burned. May not be an issue for some but it is worth mentioning.

-- Brad, Texas,

View TheGreatJon's profile


348 posts in 2291 days

#4 posted 01-10-2016 10:24 PM

I also have a detached 2 car garage. Mine has a natural gas line extended from the house and the unit is hung from the ceiling like you describe. It was installed when I moved in and I honestly haven’t inspected it closely, but it does draw the shop air through it with a fan. It’s been really dusty in there and I’ve never smelled anything burning.

Natural gas is cheap. If you can feasibly run a line, I highly recommend it. My shop warms very quickly.

-- This is not the signature line you are looking for.

View paratrooper34's profile


915 posts in 4009 days

#5 posted 01-10-2016 10:40 PM

Ben, I also live in Western Mass and can tell you that propane prices are the lowest I have seen in the five years I lived here; under 2.00 per gallon. If you own your own tanks, you can get some super deals.

Consider a two piece Heat/AC unit. Half of it mounts on the wall inside and the other half outside. Those units are a good option for heat and AC when other options don’t work.

-- Mike

View conifur's profile


954 posts in 2209 days

#6 posted 01-10-2016 10:46 PM

Moisture from a propane heater is only a problem if it does vent to the exterior.

-- Knowledge and experience equals Wisdom, Michael Frankowski

View Jim Finn's profile

Jim Finn

2878 posts in 3979 days

#7 posted 01-10-2016 10:48 PM

Look at the oil filled radiator style elec. heaters. That s what I use. No flame, fumes, danger from goofy stuff.
Might not be the best from an economic standard, but I sure feel safe with them.

- Bill White

I heat my 22×14 shop with one of these but it really does not get all that cold here in West Texas. Gets down to about 15° occasionally. I would not worry about using a Modine heater either.

-- No PHD just a DD214 Lubbock Texas

View conifur's profile


954 posts in 2209 days

#8 posted 01-10-2016 11:17 PM

The electric oiled filled heaters are the least effective/efficient based on a Consumer Reports rating, the milk house style with a fan are the most, and around WI they sell for 17.00$. I have used one in my insulated, unheated basement shop of 15×15ft and worked fine.

-- Knowledge and experience equals Wisdom, Michael Frankowski

View AlaskaGuy's profile


6482 posts in 3367 days

#9 posted 01-10-2016 11:42 PM

The only way your going to have a dust explosion in your shop from an open flame heater is to have a cloud of dust so thick you couldn’t see or breath much. So forget about that problem.

Here’s a pretty good article of different heaters for woodworking shops written by Woodworkers Journal.

-- Alaskan's for Global warming!

View SamuraiSaw's profile


513 posts in 3022 days

#10 posted 01-10-2016 11:51 PM

The shop I’ve been in for the last 2 years has a Modine gas heater that is over 30 years old. During the winter it keeps the shop at around 65 degrees with no issues. In addition to copious amounts of sanding I spray finishes as well.

-- Artisan Woodworks of Texas....

View Knothead62's profile


2600 posts in 4019 days

#11 posted 01-11-2016 06:27 PM

Whatever you buy, make sure it has a fan to circulate the warm air. Our gun club has a LP heater in the indoor archery range which is about 20X60. Turn it on and the fan warms the range in just a few minutes.
The oil filled heaters that I have seen are radiant only. Would take a long time to warm your shop. Good idea for the insulation.

View DrTebi's profile


402 posts in 4324 days

#12 posted 01-11-2016 06:58 PM

Look at the oil filled radiator style elec. heaters. That s what I use. No flame, fumes, danger from goofy stuff.
Might not be the best from an economic standard, but I sure feel safe with them.

- Bill White

That’s what I use too. It doesn’t get that cold here though. Depending on how cold it gets, you may need a large model though.

A real-life example: Due to renovation I currently live in my living room, which is about 20×12 feet, insulated, with three windows. I use a cheapo electric oil-filled heater, 1500 watts max. It takes a while to heat up the room, but once it’s warm, I just leave it on about 1/2 setting 24/7 and it keeps the room comfortable. However, it hasn’t been below 40° F here…!

This is not the most economical solution, but in my opinion the simplest and safest.
With a bit of calculation (energy cost, how many hours you run the heater, how many watts it uses) you can quickly figure out how expensive it would be.

Heaters that blow hot air are probably more efficient, but it dries up the air, blows dust around, and makes me sick…

View revanson11's profile


113 posts in 3391 days

#13 posted 01-11-2016 07:24 PM

My shop in Minnesota is 20’ x 28’ with 6” walls with fiberglass batts along with 16” of blown in insulation in the ceiling. I use a 35,000 BTW Empire direct vent LP wall heater. If I run my ceiling hung air filter when I first go out to the shop I can heat the space from 58 degrees to 65 degrees in about 30 minutes, even when it is -30 outside. As was pointed out earlier here the price of propane is less than 1/2 that of any type of electric heating system. If by chance you have natural gas in your area even better although with how cheap LP is this year it might even be cheaper than natural gas.

-- Randy, Central MN

View English's profile


690 posts in 2535 days

#14 posted 01-11-2016 09:04 PM

I heat my shop with a thru the wall mounted window unit heat pump. 11,000 btu cooling and 8000 btu heating with electric backup strip heat. Very economical. I set it at 55 when not in the shop and bring it up to 62 when working.

My shop has r15 in walls and r19 overhead. R6 on the rollup door and double pane windows.

It adds about $20 to the monthly utility bill.

-- John, Suffolk Virgina

View Ben's profile


491 posts in 3915 days

#15 posted 01-12-2016 02:44 PM

What do you guys think about a ventless propane infrared heater? There is one for sale near me used that looks good, but I know very little about that technology. Would that be dangerous around dust?


showing 1 through 15 of 20 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics