The annual shop heat thread

[John Stevenson]

Two wood burning stoves, one in the house and a big one in the workshop.
Ask any of the UK guys about the workshop one you have to run past it

The small town I live in is the heart of the UK furniture industry as in chairs and seating. Within a two mile radius of me I know of 38 different factories and I'll bet there are some I don't know of.
They use mainly beech and a bit of maple and all the offcuts are dumped, A skip currently cost £160 just to empty it what with land fill charges so they willingly give the offcuts away. This year one company has taken to delivering two big builders rubbish bags per week provided they get the bags back. This is all small offcuts about 1" to 2" cube, you shovel it like coal, goes well in the house.

Add to this the local, 3 mile away, double glazing warehouse gets their raw product in from Europe with L shaped wooden battens banded round to protect the corners, two sizes 3" x 1 1/2" about 30" long and 4" x 1" about a foot long.
Again these are thrown and I have an arrangement with the foreman that they save me these. Usually pick up once a fortnight at weekends, security know me so no problems with time.



This was this Saturdays run, the van is full, workshop stuff at the back and some of the smaller house stuff at the front where I can get it out the side loading door.
Took about an hour to travel and load this and it will last about the two weeks, any extra gets stacked as a buffer for when they are closed over Christmas.

[Jim Shaper]

I use a 100 pound tank every 2 weeks (about $60.00 I think)

Good lord... I spend 300 a year (6 months last year) heating my shop on nat gas.

[alanganes]

Anyway.....I just bought a little 1/3 hp circ pump and my intention is to sterilize a few lengths of hydronic baseboard and circulate domestic hot water through them. I think that's legal, otherwise I'm going to get the smallest gas fired water heater I can find and use it as a boiler instead of the main house HWH.

I have seen both of these things done, by licensed plumbers on legit (ie, inspected) jobs. Hydronic baseboard is just copper pipe with fins, so is no different than the supply pipe in the rest of the house.

One was using the domestic HW to add heat to a small room added onto the house, that would have been a major hassle to hook up to the main hot air system. The other, using a HW heater as a boiler was in a small super-insulated house that needed very little heat to keep it warm.

The one difference required (according to the plumber) was that if you are using your domestic HW, you need to use a circulator pump with a bronze pump head rather than cast iron. Not sure if that was a code requirement or just good practice.

[Your Old Dog]

I have a 1300 square foot shop in the barn 2x6 insulated studding but 6 large windows. I heat it with a 45BTU propane version of this:

http://cgi.ebay.com/GARAGE-FURNACE-S...item4835cbe625

I use a 100 pound tank every 2 weeks (about $60.00 I think) and spend about 8 hours a day. Mine is on a timer that cuts power to it after 4:30pm and won't come on again until I go out in the morning and turn it on. Takes about 10 minutes to heat up. Mine has a thermostate control.

This particular model has a blower in the chimney circuit which means that in most building codes you can vent it horizontally. Otherwise, you have to go straight up with the chimney. I'm using something like a 4" double wall chimney that goes 4 feet horizontally and then up through the roof about 5 feet. I also ordered the Nat Gas jets for it incase I one day want to convert. As it is, the 2 100 gallon propane tanks I bought work out just fine.

I've had wood stove and a space or wall unit but like this better.

[Jim Shaper]

Btw, that machine came to me in that condition.

Unheated is a bad idea if you have any kind of temp swings to allow condensation.

[BigMike782]

I like my Hot Dawg heater with the exception of it is on its 3rd circuit board.

[skyboltone]

Heating only you means all your machines will look like this in a few years:


It also means you'd need gloves to turn the wheels and that's simply not safe.

My shop is about 1000 sq. feet. Unfinished and a rotten stinking disorganized filthy mess at the moment. I have no idea how I'm going to get it all in there. Anyway.....I just bought a little 1/3 hp circ pump and my intention is to sterilize a few lengths of hydronic baseboard and circulate domestic hot water through them. T-stat will open two solinoids and turn on the circ. pump. I think that's legal, otherwise I'm going to get the smallest gas fired water heater I can find and use it as a boiler instead of the main house HWH.
The other option is to run a length of duct from the forced air system in the house through an electrically operated damper and set up a separate zone for the shop. This would also require a shut down damper in the main system which would be a pia given the layout. I just don't want to run the main system to bring my space to temp. I also don't want anything that sparks in the shop. I sometimes paint in there. Hydronic is the best and cheapest in my experience. For a small space, there is no need for a full whoop te do boiler.

[Jim Shaper]

Heating only you means all your machines will look like this in a few years:




It also means you'd need gloves to turn the wheels and that's simply not safe.

[dp]

I would think that heating the person is cheaper than heating the room which calls for radiant heat. What's a good way to get radiant heat from burning oil??

I know that having long, sinuous pipe running to the chimney can produce lots of radiant head and of course it also produces convective heat. It helps capture the heat that would otherwise leave the building. Still, it is smelly, smokey, required refueling, etc.

So what works best?

http://www.gerbing.com/

This stuff will keep you warm at 80 mph all winter long. Cheapest way to stay warm in the shop anyone's ever come up with. Just don't forget to unplug yourself before you head for the shower. Or get the battery powered version.

[Jim Shaper]

I've got R30 in the walls, and no less than R60 in the ceiling with exception of the 4sf opening for the fan (shuttered when not running), and the 3sf access panel.

Wood blocks? Surely you jest.

The contact patch of any of the machines feet is so small it wouldn't make a lick of difference.

I do actually plan to install a recirculating fan. Been looking out for a decent cheap one for 6 months.

[Evan]

How much more it costs to keep it at 65 depends on the ratio of the outside temperature to 55 vs 65 degrees. If the outside is 45 then 65 is twice the number of degrees difference of 55 and will require twice as much heat to maintain the higher temperature.

It also depends on how often you raise the entire shop to 65 vs leaving it at 55. Raising the temperature requires more heat input than maintaining the temperature at any particular value of temperature. This especially applies to raising the temperature of the thermal mass. This extra input is offset by the time it takes to cool when the thermostat is turned down. It takes no heat input at all to let the temperature drop.

And, that is where insulation comes in. The better the insulation the longer it takes to let it fall. Insulation doesn't make much difference to the time it takes to raise the temperature but it make a big difference to the time it takes to fall. Insulation makes a greater difference to maintaining temperature the greater the difference between outside and inside temperature.

If your shop is slab on grade you can keep it warmer by placing the machines on blocks of wood. That will stop a lot of conductive heat loss through a cold floor. You can reduce overall heat loss by circulating the air with a fan. Because hot air rises the temperature difference in stagnant hot air in the upper half of the structure will lose heat faster than if the same amount of heated air is well mixed resulting in a lower inside/outside differential.

[Jim Shaper]

Considering I have at least 20Klbs of iron in the shop, the thermal mass keeps the temp pretty stable even in the dead of winter.

I leave the heat at 55F and the heater only runs a couple hours a day in January to maintain that. Then I bump it up to 65 when I'm out there.

I'm contemplating raising it to 65 all the time to see if it even changes anything in fuel consumption. I have the hobbs meter on my t-stat so I can see what the run time for the current and prior day is/was. It also keeps track of the total time so I know what my energy cost was for the season when I shut it off in the spring.

[JRouche]

If you live on southern ca. you do not have to think about it, a cold day is 58 Brett

Im a wuss!!! Im in So Cal and I dont even want to get out in the shop before noon cause its all metal, and cold.

So I run into a dilemma. If I run the heater in the early morning, before I get out there to do some work Im heating the whole shop up. It gets nice and toasty. I keep it heated for the day then shut her down at night.

It takes at least two hours for the temp to come up in the morning. Kinda like an endless cycle. Should I keep the temp all through the night. So where the heater is just idling to keep it nice. So in the morning Im not putting it on full blaze for two hours just to get it back to a decent temp..

Im looking at where the trade off is. All night at an idle, or two hours on full go every morning then an idle after that for the rest of the day. And OK.. Didnt want to say it. But Its an electric heater, big 220vac unit. I cant afford to mount a gas heater right now. Maybe. They are pricey..

And yes, Im cold blooded, living in so cal you are thinking WHAT!! Why do you need heat. Im cold.. JR

[Brett Hurt]

well the heat

If you live on southern ca. you do not have to think about it, a cold day is 58 Brett

[Boucher]

Heating the shop

Since retiring in 2003 and moving into a smaller home shop I just bit the bullet and installed central air/heat. Sure is nice. The old shop 40x80 was heated with a large wood stove burning 2x4 lumber that came banded on lifts of pipe and saved throughout the year. We ran an oil injection burner to dispose of oil collected throughout the year as well. I used a single 21' joint of 6 5/8 steel pipe for the flue. The top of the stove was 1/2 steel plate for the pipe to set on. The injector tube was coiled around the flue for preheating the oil. The amount of time the system ran worked out about right for the materials that we need to dispose of. On a cold day everyone that came in wanted to back up to that old heater. It sure felt good but it would get hot enough to make you rethink your standoff distance.