I live in a condo and own the right two bays of a four garage building. My units are separated from the other two by an uninsulated wall that extends up to rafters. The rafters are completely open across all four units and there are no ceilings (roof yes, ceiling no - just to be clear).

Last year I bought one of those 60,000 BTU "jet engine" forced air kerosene heaters. It did a decent job of heating things up despite the openness of the garage, as explaned above. The major problem is that this heater produces a lot of fumes and that I could only get the temperature up to 50 degrees on moderately cold days (20 degree outside temp).

This year I have closed off the ceiling with plastic and have made a "curtain" of the same plastic to cordon off just one of the garages. The hope was that even this amount of effort to keep some of the heat in rather than trying to heat up all four garages, would yield me good results.

After all that, the question is whether a smaller 23,000 BTU kerosene heater will do the trick for me? The reason for wanting to move to the smaller heater is that it burns much cleaner, ie no or almost no fumes.

Anybody have any experience that they can share?

Ed

I believe if the 'jet engine' didn't heat the one stall, then the k/heater isn't going to do it either.

The jet engine has a blower to circulate the air. The k/heater works on radiation, no blower. Kerosene is still going to produce fumes. I'd go with a propane heater, these are very efficient and need no venting to the outside, plus add some moisture to the air.

Go with a propane heater. Summit Racing has them on sale in their on-line catalog.

I have a couple of those small tank top propane heaters. The problem with them is that they are radiant and hence you get "the dark side of the moon" effect - the side facing the heater is roasting and the other side is freezing.

Everett, you think the smaller one won't do the trick. I am guessing the larger one will now that I have closed things off a bit. I can test this theory this weekend as we are going to be in the thirties. With respect to the fumes, I used to heat my apartment 20 years ago with a kerosene heater. This was before they were deemed to be too dangerous for indoor use. I never noticed the fumes except at start-up. I took to starting it outdoors and then carying it in. Thereafter it was great. The 'jet engine' seems to produce fumes at all times. Maybe there is something wrong with the one I have or maybe that is just the way it is.

Ed

Ed,

I use a 50k forced-air in my 2-car and other than the freakin' noise, I don't really notice the fumes. I buy the smokeless\odorless fuel and pour in a Christmas scented additive. (I know... corny)
Mine will only bring the shop to around 60 when it's 30 degrees outside but that's with the rafters open and the roof vent (spinning ball on top of 10 inch dia. vent) open.

I made a 'ceiling' with plastic and a small hole to vent but I don't know how well it's going to work yet as it hasn't been that cold lately. I always leave either the front or the back door cracked for fresh air and have the rear inlet side of the blower in the dog door to get fresh supply. I'm sure that 50k will be MORE than enough for that 2-car space now with a 'cieling' in there. I'd imagine a 23k kerosene would be sufficient. A radiant type might work if it's large enough to heat the entire space and keep it heated, but I like the forced-air because I can run it till the shop is warm and then turn it off. Radiant might have to be run constantly.

Please be safe with these heaters! I'm not familiar with these types of heaters but if I can add a word of caution here. If these are open flame type heaters you have to be adding more fresh air then you are burning or you will be adding dangerous levels of CO to your garage if the appliance is not vented to the outdoors. If these are cat. heaters (gets heat by oxidation process) then you are okay with what you are doing. Sorry for the ranting but I'm not familiar with the heater you are talking about but have seen and heard too many CO poisoning cases. - Barry

I have a 110,000 BTU kerosene torpedo heater.I got it on sale in the spring at Home Depot for about $250.I run it for about five minutes at a time and it will bring my 25x25 insulated garage to 70 on the coldest day no problem.I want to get one of those thrermostats to cycle it on and off automatically.I had a little propane torpedo that ran off a barbecue tank.It didn't heat up the gagrage that well and it cost about $15 to fill it and its a pain to get filled.$15 worth of kero will last me two weeks in the dead of winter where one tank of propane would last a few days.I probably spent more on filling the propane tank in one winter than i spent on the new kero heater and all the kero i used the next winter!Thats a good point about CO poisoning.I keep a window cracked just in case.

I have to agree with HwystarJoe... cover those rafters ! Use at the very least plastic sheating for a low ceiling and angle it downward so any condensation can run down it. You then can try your form of heat. Remember to keep it well ventilated !

Here's the formula, but it's a little long:
Assuming a 24'x24' space results in 576 sq. ft. At 1.44 CFM (cubic feet per minute of forced air) you will have 400 CFM. 400 CFM X 50 degrees rate of rise (the amount of air temperature rise from ambient) X 1.08 (specific heat) equalls 21,600 BTU's. (400 X 50 x 1.08 = 21,600.
This formula assumes NO air exfilteration or infiltration and a cement block wall with no insulation. It would raise the internal temperature from 20 degrees to 70 degrees in one hour if 400 CFM was pushing it. If it gets colder in your area than 20 degrees, substitute a larger number for the 50 in the formula. i.e. 0 degrees outside, substitute 70 for 50. You must make allowances for steel garage doors, walk in door and windows. (Add 3,000 BTU's for garage doors, 1,000 BTU's for walk in doors and windows. It WILL not account for a cold floor (add approximately 5,000 BTU's for a cold concrete floor). Hope this helps.
PS. DO NOT use Kerosene without exhausting the fumes. EVER.

Thanks Toby,

You're right about the floor. A garage floor is just a few inches on concrete on the frozen ground. Unless you're Jim (Click) and have radiant floor heat, it'll always be cold. ;)

I finally got a chance to run my forced-air 50k unit this weekend. It was in the 30's outside. (I hate NY)
With the plastic ceiling in the shop now as opposed to the open rafters..... WOW! It heats up real fast so I don't have to run it as long. The downside is having to keep one of the doors cracked open to vent. Mother Nature sucks my heat right back out. I think I'll play with the ceiling opening some more.

Before I put a 'ceiling' up, the wind would rush in through the home-made dog door, so between that and the roof vent, I'd get good circulation of the air in there. Either one direction or the other. I can't run one of the heat registers in there from the house furnace for a couple of reasons. If I could have, I would have already. :(

Over kill, but I bought a natural gas hanging furnace from a friend of mine, 130000 output BTU. The garage is 24x28, insulated and sheetrocked. My brother told me I could bake bread in it, no I said just paint. ;) I only run the furnace when I'm in the garage.