What’s the best and safest way to heat a gargae shop that attached to my house? I just bought a propane contractors heater and now see all kinds of warnings.
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Hello Montana from Calgary Alberta,
We have similar weather up here so I think my solution could possible work for you too.
I plugged in a 4800W Dimplex construction heater, which was bought at Home Depot for $55 dollars. The unit is a metal box about 12" square, with a heater core and a fan to blow the warm air out into the garage; therefore, this warms up most of the garage equally. I hung the unit on an angle bracket 1 foot away from the wall and 4 feet off the ground. Our garage is well insulated with R20 in the walls and R40 in the ceiling.
This electric heater warms up my shop located in our double attached garage and has been keeping things warm for 6 years. It has a dedicated 20 AMP 220 V line run to a plug in that looks exactly like our dryer connection. The heater has a manual setting type thermostat on the back that sets the heat from level 1 to 6. In the winter I keep the setting at level 2, which equals 40 F, but 15 minutes before going out to work I crank the thermostat up to 5 and I enter a warm 70 F workshop. Our electricity rate is $0.07 per KWh, so the warm shop costs me $50 per month in the dead of winter. The unit was easy to install, is cheap to run based on our local electrical rates. The heater only requires a cleaning with the compressed air every other month to get the dust off the blades of the fan.
Hope this helps.
Bob in Calgary
Bob in Calgary,
Many thanks for the thoughtful reply. Yes we do have similar climate patterns. I have looked for the heater you recommend. I can only find either a 4000 watt or a 10,000 watt version. My garage is 25X19' and insulated to no more than R19. Do you think your heater would do the trick?
Montana,
Before you jump at the construction heater I must give some warning. Oddly I live in Calgary, having moved here from Fort Saskatchewan 8 years ago! For the record Calgary weather is much nicer than the Fort...
I had been using the same heater for heat in my garage. It works, but I don't think it should be left unattended. My heater blew up spectacularly last year, and could have cause a serious fire had the shop not been clean. With an attached garage safety is even more important. I would use the heater again as long as I was in the shop, but I'd never leave it unattended.
If you want to use electrical contact an electrician and see what they have. I looked at a few heaters, that were meant for running for this application. They cost a little more, but it's a matter of safety.
I installed a Natural Gas heater in the shop/garage and I don't regret it. The upfront costs are more, but it's a much more reliable heater. It is after all what there designed for. As an added bonus, I was able to recoup the cost when I sold the house in September. I also found that the cost was much less than electric, I estimated $50 for electric, maybe half that for gas (It's hard to say). I just got a quote this morning for a new one for the new shop, $2600 (Cdn). Not cheap, but in the long run well worth the money. As well if your shop does do double duty as storage for your wife's car... It's an easy sell!
I installed my own in a day with a total cost of about $650. I love it and having a warm vehicle on a -10 degree morning is fantastic.
Rob
Buster, did you ever figure out what caused the heater to "blow up"??forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Buster, did you ever figure out what caused the heater to "blow up"??
Nope. It was part of my clean up routine to use the compressor to blow it out. So it was clean.
I suspect it was either a faulty unit, or that it was just running too much (it was during a vacation period for me and the weather was very cold -25C). Either way that doesn't really place the heater as a very safe choice for regular shop heating. Rightly so, these heaters are meant for the job site.
I just got a pleasant surprise.
I have a 22 X 20 insulated garage with 11 foot ceilings.
I have been using a 3000 watt shop heater. It’s wall mounted with a fan.
I’ve had one of those electric oil filled heats in it’s box in the basement for a while. Used it at our old house for my smaller shop.
I did’t run the wall heater all the time I would just turn it on and wait a hour for the chill to come off.
Well I thought maybe the oil filled would keep the space a little warmer between shop sessions. So used the wall heater to bring the space up to 65 or so, set up the oils base heater and left the shop.
It’s been a week and a half and the temp has not dropped below 63.
The heater is a 600-900-1500 watt unit.
I don’t know how often it cycles on and off yet. I’ve ordered a Kill-A-Watt to plug it into to see how many watts per day it uses to be kept on.
I've used those as individual room heaters in various houses for years. I can't remember the number of units I've went through. They are pretty cheap and heat small spaces well and are pretty safe. The only down side is when that thing is running at 1500w go outside and watch that meter wheel run, it's amazing! If you press your ear to the glass on the meter you can hear a faint cha---ching!! Government's view of the economy could be summed up in a few short phrases: If it moves, tax it. If it keeps moving, regulate it. And if it stops moving, subsidize it.
Anyone using a propane heater should know that it is illegal, and totally foolish, to keep any propane cylinder larger than 1 pound inside of an enclosed space. A leak from a larger tank will quickly fill a building with enough gas that, should it ignite, will reduce the structure to kindling. Another risk is that a large tank will feed a fire started by some other cause. Tanks have pressure safety valves but they will be venting into the building if they get exposed to the heat of a fire.
I'm not sure what an insurance company would say, but I would guess that they might not be inclined to cover the costs of a fire started by using an illegal heater and tank combination meant for construction sites only.
Pound for pound, propane has about the same explosive power as dynamite, so it needs to be respected.
John White, Yestermorrow School, Waitsfield, Vermont
So anyone and everyone that ever put a large tank from a BBQ in the garage is breaking a law and setting themself up for issue with the insurance co.?
Doug
Basically yes, and if you've ever seen the aftermath of a propane explosion, you would never stash a tank in your garage. As to the insurance issue, call your insurance company and ask them.
John White, ex EMT and accident investigator
Edited 11/30/2007 2:26 pm ET by JohnWW
Well I got the Kill-A-Watt today and plugged the heater into it.
At the 1500 watt setting it will cost $22.50 a month.
Montanaman
The 4,800 watt works in my space, but your shop is almost 50% larger than mine and based on that fact alone I would opt for the larger unit rated at 10,000 watts. The unit would heat up your shop quicker than the smaller unit and based upon your amount of insulation, probably the larger unit would run less often - so probably it would be just about as cost effective.
I have heard about Buster's problem when their electric construction heater blew up and could have been potentially a huge disaster. I asked my commercial electrician neighbor about he situation and he said there are some much more expensive units with superior safety features - but the key aspect is how often does the unit cycle and how clean is it?
My electric 4800 watt heater is running about 10 minutes per hour at -12 C (sorry I grew up with Fahrenheit but I have since forgotten the conversion) today while I am out in the shop. So it is cycling maybe 15% of the time in the dead of winter - not excessive for a construction grade heater - yes these are construction grade heaters used on the job sites around here. Secondly I clean my blades off regularly with the air hose so there is no build up of dust near the heating element which could easily cause a problem.
Buster is right though and if I had unlimited funds I would have a nice radiant heater in my shop! For now the small electric construction heater will do the job quite nicely - and it has worked well in my situation for going on 7 years.
BUY THE BIG UNIT at 10,000 watts and enjoy the heat!!
Bob in Calgary
If that propane heater operates off of a BBQ tank, the biggest problem you'll have (in Montana) is that the tank will get too cold to operate before your shop gets warm! I had one for awhile, and besides being incredibly noisy (that would be the "torpedo" style), the frost on the tank would build up so fast! IMHO, one needs a big propane tank in really cold weather, so that the frostyness isn't a problem.
There are many people who wouldn't use an open flame in a WWing shop. I'm not one of them. Currently have a pellet stove (which is having problems, dhamkit). If codes (and budget) permit, you could consider a woodburning stove or pellet stove. Otherwise, the ceiling mounted heaters of various kinds would be my choice. Kerosene and propane will increase the moisture level in the room, so keep that in mind.
Jamie, surely your pellet stove is vented. It would, of necessity have to be. The torpedo you speak of would not be vented, which is okay if used as designed - no windows or doors installed. I wouldn't suggest using the torpedo or any non vented stove in a tight building. With the vent, both the noxious gasses and the moisture are expelled. Where I grew up we had an oil stove that would dry out the air so that your nose would burn, your skin would get all itchy. And, of course, that was in a pretty dry climate.
Yep,the pellet stove is "vented" (therein lies the current problem, which we're fixing. Flue got messed up). I've used three different propane heaters in my very untight shop: a torpedo, a tank-top radiant attachment, and a Mr. Heater double-cannister. All three had problems with the tank frosting up rather quickly in cold weather. Never ran them long enough to have an impact on moisture. Also ran a kerosene heater in there, but it was the wrong type (radiant) for the purpose.
There are a number of blue-flame ventless heaters out there, not that I'd use them, but would they not contribute moisture to the air?? As would the convection type kerosene heaters.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Edited 11/25/2007 11:02 am by forestgirl
Yes, any unvented fuel burning appliance will add moisture to the air - plus all the other byproducts of combustion. The "unvented" gas heaters are tuned to burn exceptionally cleanly when operated and used exactly as spelled out in the manual. However, I'd never use one in my shop. The moisture issue would be a deal-killer, as it would undoubtedly create tool condensation and wood movement issues. Plus I have no desire to breathe in any more substances than I already am out there.
I'd also be wary of using an open or exposed flame heater in a shop environment. Not only could things catch on fire, but dust and debris settling on the burner could produce an impingement of the flame - and that leads to excess carbon monoxide production.
For me, a Empire direct-vented gas heater works well (or would if it had been sized correctly - it's actually too small for the space I have). But there's no open flame, and all the combustion byproducts are vented outside through a wall-mounted double wall pipe that acts as both a vent and combustion air intake.
Zolton* Some people say I have a problem because I drink hydraulic brake fluid. But I can stop any time I want.
Zolton,
Your sign off tag line is very funny! Love it.
TT
"There are a number of blue flame ventless heaters out there, not that I would use them, but would they not contribute moisture to the air----."
You bet they would. Anything that burns a hydrocarbon releases water and has the potential of producing CO. A proper vent system should evacuate these waste products to the outside. In my town, it is illegal to heat with a ventless heater in living quarters. Having been in the apartment business for some years, I know that an inspector would condemn an apartment on the spot and not allow occupancy until the thing was properly vented.
In practise, I think a very, very untight shop would be okay. But who am I to test it out?
On a personal note. I think I'll pass on those past FW magazines, for now, anyway. I have so much reading material to catch up on. I'm rooting for you though, to get enough saved away for that SS though.
Paul
Edit: Forgot to mention a system I made while building a house out in Nebraska years ago. I made a weed burner from a cylinder about ten inches long and three inches in diameter, cut air holes in it and attached it with a hose to a 100 lb. propane bottle. It would put out a blue flame for about eighteen inches and would heat the 1500 sf uninsulated house from 10° to 70° in sixty seconds but then the bottle would freeze up and could hardly keep it warm through the day. Even though the air was 70°, all the woodwork was still cold and it didn't really feel warm in there. A friend of mine made one and would put the flame right on the bottle to warm it up. I wasn't quite that brave.
Edited 11/25/2007 9:39 pm ET by Tinkerer3
"On a personal note. I think I'll pass on those past FW magazines, for now, anyway." I dropped the ball big-time on that one, didn't I??! I remember making a note on my calendar for when Nick was gone hunting, to look for those mags. Then he didn't reallllly get away (just for a day and a half, not enough for me to get down to my own stuff). Reallllllly sorry about that!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Montanaman
I am a little south (utah) and i have been using one of those propane heaters for years, Works great just keep it in the open floor and dont sweep up the wood scraps next to it and you should be fine.
On cold days i usually fire it up and then go in the house for a quick cup of coffee while things warm up a bit. Today it was in the high 20's out side and once the heat started up it was very pleasant mid 40's to work.
Make sure your well ventilated.
Look here: http://www.empirecomfort.com/ I have one in my garage/shop that runs off of nat gas but they come in a propane version as well. It's perfection. No affiliation. - Kris
I heated my garage shop for 20 years with a milk house heater from McMaster Carr. It operates on 220v and is rated at 3000watts. Has a three speed fan and thermostat. Keeps my shop 65 t0 70 degrees F. when it was -20 out and the chill factor was -45. the shop was 14 x 26 with 10 foot ceilings. All walls & ceiling were well insulated and the 9' garage door was ot insulated but I kept a couple of sheets of plywood against it in the winter to sort of provide some insulation. Here in Ohio it would cost about $0.36 per hour to run if it was on all the time which it hardly ever did as it would cycle off and on as needed. Elements never glowed red , only got a straw color under the most severe heating requirements. Has a automatic turn off if it gets tipped over.
Edited 11/25/2007 10:11 pm ET by mrbird90
Like Bob in Calgary, I have been using a 4800 Watt electric construction heater. My home is in Fort Saskatchewan slightly north east of Edmonton, Alberta. My shop is a modest 15' X 25' with a 10' ceiling. I have 6" R20 walls and an R80 ceiling. The floor is uninsulated concrte. This will change in 2008. Once I am out there working, it warms up very quickly and I usually turn the heater down.
If your propane heater is not vented it will produce all kinds of water vapor and deadly combustion exhaust. If you vent the area to ensure you have enough air, you will still have the condensation to deal with.
My recommendation is to insulate first, heat second.
Good insulation, like any good tool, is a one time cost. Invest properly in this item and reap the rewards year after year. I was going to put in one of those radiant gas burning tubes, but the shop is fine with the current arrangement.
By the way - when it comes to cold I am a total wimp.
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