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Tomzhere
11-05-2003, 09:08 AM
Time to heat the shop. I have a drafty (due to overhead door) 600 Sq. Ft workshop that I need to heat this winter. I'd like to hear your suggestions regarding heater types and learn how others do this.

I need to keep it economical and safe. Most of the time, I only have to deal with temps in the lower 30's.

Do you heat your shop overnight? Also, keeping floor space to a minimum would be great too.

pgmrdan
11-05-2003, 09:36 AM
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[This message has been edited by pgmrdan (edited 11-16-2003).]

Tomzhere
11-05-2003, 10:37 AM
pgmrdan
I have a kerosene heater of the type you refer to. But to get any heat you have to hoover over it. Definately does not heat the shop.

The winters are mild here but my shop helper (wife) still gets cold in the winter. Don't want to lose her help : ) this winter.

Still sunny and in 80's today though : )

debequem
11-05-2003, 11:06 AM
Hmm, I would think that ideally you want to maintain the temperature and humidity inside at a constant year round. Better for the tools and tool accuracy, I would think. Also, moisture and oxygen will rust steel!

I hate the cold, so I would fix the draft, insulate like crazy, and make sure I have a controlled fresh air system.

Oh, I have my shop in my basement, so temperature is always constant. Just wish I had as much room as you do!

Insulation helps year round. Once the place is tightened up, then heating and cooling should be reasonable to achieve. Just remember that you need good breathing air inside such a small place, so I be concerned about heating systems that burns inside oxygen (wood kerosene, etc). My preference is that you come first when competing for the oxygen.

Of course there are heaters that draw their air from outside (some wood stoves, etc.).

One advantage to keeping the heat and AC running all the time is that the machinery is always at the right temperature when you go to use it. No need to worry about temperature coefficient of expansion or chattering teeth to disturb your fun. My motivation drops to near zero as the temperature drops. I don’t know about you.


[This message has been edited by debequem (edited 11-05-2003).]

Evan
11-05-2003, 12:02 PM
Speaking of near zero it is 1.0F here this morning. So much for working in the garage very much. Good thing my shop is in the basement.

I wouldn't recommend using those indoor kerosene or propane heaters in a shop. They do make safe ones but they put out large quantities of water vapor which will condense on cold machinery. Rust-o-matic. Either use electric or vented gas or oil. The best shop heaters are the overhead natural gas radiant heaters. They must be vented and you need a high ceiling, at least ten feet as well as natural gas or propane. They also cost $$$ but work very well. They are available with lighting built in also.

pgmrdan
11-05-2003, 01:57 PM
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[This message has been edited by pgmrdan (edited 11-16-2003).]

Yankee1
11-05-2003, 02:49 PM
Hello
I bought a radiant heater from Lee Valley
Tools for 69.00. It does not heat the air but works like sunshine.There are two elements that can be used together or only
one. I live in Oregon.Temperature is anywhere from 30's to 50's when I work in the shop.The heater mounts on a bracket that
mounts overhead on the rafters. It is one of
the best solutions that I have found.Keeps
me warm instantly.Very inexpensive to operate, cost a maximum of about .16 cents
per hour.My kerosene heater was expensive
to operate, this is far better and safer.No
filling and storage problems.I stand at my lathe or milling machine in the warm radiant
heat.Lee Valley is great to deal with.
Regards yankee1

Tomzhere
11-05-2003, 02:57 PM
Evan
Thanks for the information. I did not consider the moisture put out by kerosene heaters. Exactly what I want to avoid.

If money were no object I would lean towards a Canadian made Radiant heater called EZ-Duzzit or a natural gas heater from Hot Dawg.

The last is more affordable. A friend mentioned a Heat Pump might be a good choice for this area. Any thoughts on that? I bet they ain't cheap either.

Evan
11-05-2003, 03:07 PM
For your area a heat pump would be fairly economical to run but they are expensive to install. With an outside temp of 50 degrees it would give at least a three to one saving over pure resistance electric, in effect cutting the cost vs electric to 1/3. Once the temp falls to the low thirtys the efficiency drops quite a bit but never less than 1/1.

I forgot to mention that most air to air heat pumps work both directions, meaning that in summer it would be an air conditioner. That should make it a lot more attractive in your area.

[This message has been edited by Evan (edited 11-05-2003).]

Joel
11-05-2003, 03:08 PM
For any heat source, you would be wise to get rid of the drafts or you are throwing $ away. Insulate your overhead door, kits are available or just cut foam to fit tightly. Seal the perimeter also, garage door installation places sell long strips with a wide sealing edge you can simply nail on. They seal surprisingly well and this makes a big difference. Judicious use of caulk and expanding foam should finish the job. If you have access, insulate the ceiling (at least). Northern sells propane and natural gas heaters for a very reasonable price. I program my thermostat to keep my shop at about 58 overnight in winter.

bernie
11-05-2003, 03:21 PM
In my shop I have a Chevy (approx. 18" X 24") 3 core radiator with home made plenum that connects it to an old furnace blower. It can be -40 here for weeks and it don't get cold in there. The shop is 24 X 24 and has a drafty overhead door as well. The hot water comes from the nat. gas boiler (167,000 Btu's) in the house via 3/4 inch lines.

It seems to be very cheap to run, quiet, clean and almost explosion proof.

Bernie

Paul Gauthier
11-05-2003, 03:47 PM
I use a an oil fired hot air furnace. takes up about 9 sq.feet of floor space and I can move out of the way and put a wood stove in its place when I have a enough scrap wood to burn. I do not leave it on overnight, only when I am out there. Condensation is a big consideration, consequently I use a lot of WD-40. It is a two car garage with a full second floor, (woodshop), The furnace does just fine.

------------------
Paul G.

zim
11-05-2003, 04:20 PM
12°F here last night. Saw a guy that had rigged up a used (read: free) clothes dryer as a heat source for his shop. Ditched the drum motor, just used the blower and heater parts. Still have to pay for power though.
Zim

John Stevenson
11-05-2003, 05:06 PM
I have a sawdust burning stove. I'm fortunate in that I live in a small town that has a lot of small firms making chair frames.
No one seems to now why but there are about 40 in this small town alone.
Because of this there are loads of beech offcuts and shavings available for free.
In fact the shavings you can even get delivered free to save them having to pay for expensive skips to dump this.

The stove is unique and was designed by Arthur the mad profesor. No moving parts or fans, you just dump a large plaggy bag of shavings into the top, it holds about two dustbins full at a time. A bit of diesel on the top and light it and it's away and you can't stand near it when it's running.
Some pics are at:-
http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/woodstove/
These were taken just before last years rebuild, at this point it had been running for 6 years.
Basic construction is an octagonal shape with vertical gaps at 4 places, 2" from the bottom to 2" from the top. These are covered on the outside by folded channel bolted thru the case. On the inside are 4 louvered plates. The original ones were cast iron with the louvre cast in but differances in expansion rates caused these to crack. Cracks are no problem but later on pieces fell inside and this affect the burning. You can see a damaged one in the inside picture on the left.
New ones are 1/4" thick steel plates with a 'U' shape laser cut and then bashed out at the bottom to form the louvre, these don't crack or break.
The folded channel is also the feet and its open at the bottom for air, closed at the top.
How it works is you light it and the whole of the top surface burns, this causes the shavings underneath to get hot and produce a gas which is forced out thru the louvres into the channel. Draft of burning then takes this gas up and out thru the exposed louvres above the sawdust level. In effect you have a swirling motion, when it's burning you can actually see this circular swirl effect. This causes it to rapidly burn down in the 4 corners. The unburnt middle then drops into these ratholes and that is burn until it gets lower and gradually goes out.
It takes about 3 hours to burn one charge.

It's biggest drawback is reloading when hot.
If you open the top and dribble a new bag in, it can flash up if it's not too low but if you just dump a whole bag in, bag as well than it puts it out and you relight from the top again.
Once you get used to it it's not a problem but I thing you would have a hard job selling one.
There is no grate in this. No air enters from the bottom, only the side louvres.
It will burn wood, paper, leaves, garden rubbish but it can't burn any fossil fuel like coal or coke as that requires a thru draught.

We are now in it's seventh year and this heats my shop all winter which I use commercially and it's not insulated as yet, not got roundtoit.
Since putting this in I have got rid of condensation problems, I feel it's because I can keep the temperature up above a certain point even thru cold nights.
I never oil up now other than working oiling.
If anything it can get too dry as I loose more coolant out of the machine tanks than I ever did before.

John S.

Evan
11-05-2003, 05:20 PM
John,

That looks like something out of the 19th century! We have wood pellet stoves here. Sawdust is compressed to small pellets the size of dry catfood. The stove has an auger feed to the combustion chamber which may be speed regulated (electric) to adjust heat. A charge will run for at least eight hours.

motorworks
11-05-2003, 05:28 PM
John
"I have a sawdust burning stove. I'm fortunate in that I live in a small town that has a lot of small firms making chair frames"
What about insurance?! Here in Newfoundland there is lots of fire wood,but the insurance on your shop would be very $$,that is if your could get it with a wood stove in it.
I use a propane heater. Propane is 22.00 for 20lbs,Lasts about a week.
Been a mild Fall so far. So no heat on yet!!
eddie

winchman
11-05-2003, 06:40 PM
I've got an electric heater in my well-insulated shop. I turn it on when I leave for my morning walk at 5:30, and turn it off when I get back at 6:30. That's usually enough, except for the coldest days.

I used to heat the shop with a small geothermal heat pump, but the heat mode quit working. I figured I could heat with the straight electric heater for a LOOOONG time for what it was going to cost to have it fixed.

I got the electric heater from a neighbor who was putting it out in the trash.

Roger

John Stevenson
11-05-2003, 06:55 PM
Evan,
It may look like something out of the 19th century but I work in a 19th century shop, nearly, actually an old stable block built in 1900.
So far I've had this 7 years and and all it has cost me is 4 new louvere plates.
This runs 5 - 6 days a week, 10 hours a day and it's very warm in the shop.
So far except the louve plates the fuel bill for seven years has been $000.00, zilch, nil, and they deliver my fuel for free http://bbs.homeshopmachinist.net//biggrin.gif
Laugh all you want http://bbs.homeshopmachinist.net//biggrin.gif

I have been running now for about three weeks, if it's mild I'll let it burn out about midday.
Trouble is with about 30 tons of machinery and steel stock it takes a lot of heat to keep a constant temperature. Once I can get it warm it stays warm.

Eddy, No problem with insurance but we don't have timber buildings here. All ours are brick, block and tiles.
There was a spate of timer framed houses put up in the 50's but these are fast disapearing as the insurance companys don't like them.
They also absolutly hate those space eaters, especially where moving vehicles are involved.
I don't think any commercial policys will accept one of those now although they are still sold.

John S.



[This message has been edited by John Stevenson (edited 11-05-2003).]

JCHannum
11-05-2003, 07:35 PM
Isn't the saying "Pretty is as pretty does".
I think I see a spot of floor in front of the stove. Might want to check that out.