Heating Two Rooms with One Appliance

[Smiles79]

Currently in the daydreaming phase, but one day I would like to build a 30x50 shop with two 8'x8' insulated offices (size isn't what is important here, this is just what I'm thinking at the time.). These offices will be next to each other and share a wall, but separate.

I plan on using a propane heater to heat the main portion of the shop, but I would like to be able to control the offices separately from the main shop (but the offices do not need to be heated/cooled independently of each other). I originally planned on using an in-wall space heater and a window AC unit. When the decision was made to go from one larger office to two smaller offices, I thought it would be a little annoying for each office to have it's own space heater and AC. A dual zone mini split seems like a good idea, but I'm in Northwest Missouri and we can definitely get down into 10 below weather at some points during the winter and I don't think those function well at that cold of a temperature.

Any suggestions? Has anyone else done something like this?

 

[fitter30]

They make hyper heat mini splits down to -13. They are not inexpensive. Since this will be tied to the shop will there be a lot of dirt? Minis don't handle dirt well for the filters are thin and the coils are tightly spaced and enhanced. Haven't look to see if they make hyper with ducted air handler. Check with your electric company for rebates and your tax person for energy efficient equipment.

 

[Shiftless]

Heat for an insulated room that is only 8x8 should be within the ability of a portable space heater. Small portable with a little fan or long and low baseboard heater tucked in at the bottom of a wall.

 

[Jackfre]

Check out Tjernlund Products Airshares.

 

[BillK]

Is the main part of the building going to be kept heated and cooled ?

 

[Smiles79]

Heat for an insulated room that is only 8x8 should be within the ability of a portable space heater. Small portable with a little fan or long and low baseboard heater tucked in at the bottom of a wall.

Yeah, I was just thinking of a way to not have each office have it's own heat and AC. And I'm not positive yet on the size, it may get bigger. Baseboard heater is a good idea! Would it be possible to have it pass through a cutout in the wall so it can heat both rooms?

Is the main part of the building going to be kept heated and cooled ?

The main shop will be heated (though just to 40 or 50 most of the time and I'll bump it up when I'm out there) but not cooled.

 

[Shiftless]

Baseboard heaters are not very expensive. Instead of a bigger one to possibly heat 2 rooms with some kind of hole in the wall with blower fan, I would just get a smaller one for each office room. Heat rooms only when occupied. That saves you more than a few kilowatt hours of electricity. Plus if one user likes 68 degrees and the other one likes 78 degrees, both of you can stay happy.

 

[Smiles79]

Baseboard heaters are not very expensive. Instead of a bigger one to possibly heat 2 rooms with some kind of hole in the wall with blower fan, I would just get a smaller one for each office room. Heat rooms only when occupied. That saves you more than a few kilowatt hours of electricity. Plus if one user likes 68 degrees and the other one likes 78 degrees, both of you can stay happy.

Yeah, that's a good point. I plan on using wifi thermostats for things wherever I can so I was thinking about ease of doing that, but separate baseboard heaters is probably the way to go.

What about cooling? Same deal, a separate unit for each?

 

[Shiftless]

The smallest 120 volt window mount AC units are plenty strong enough for an 8x8 room.

 

[jblnut]

The smallest 120 volt window mount AC units are plenty strong enough for an 8x8 room.

I have an el'cheapo 5k BTU window AC in my 12x16 office and it is more than enough. I actually put one in the main shop (54x72 minus 12x24 office/mech room) and it does so well that I'm not going to put an "actual" AC in there. It's keeps the humidity down and this summer the shop rarely got above 70F. It ran roughly 12hrs a day almost nonstop from 1pm to 1am drawing something like 350w. Something like $0.65/day to cool isn't bad in my book. No idea how it does so well but I'm not complaining.

I'd second the baseboard heater solution in each room as well. Not the least expensive source of heat to operate but they're cheap to purchase and will be perfect for your use case.

 

[Mzungu]

With an 8 x 8 insulated room you could easily heat it with 250 watts. One of those flat panel wall heaters would be a very economical option. I heat a well insulated, larger pump room (8 x 10) with a Honeywell heatbud set on low, controlled by a line voltage thermostat.

 

[Smiles79]

Thanks everyone. My question here is how hmi can heat these two rooms with one AC/heater, but I appreciate the input anyway.

 

[Shiftless]

Here is my input on that point.

Yes, I realize that you want to have just one unit to heat and cool both spaces. My earlier suggestions were ideas to try to change your mind and provide individual control and save on energy costs. But it’s your place and of course you can do what you want,
A friend of mine bought an old rustic house that was heated by a wood stove In the kitchen. It had a through the wall electric fan to blow some of the heat into an adjacent room. The door between the rooms had a big gap to provide return air. Once the wood stove was going strong and the kitchen was warm, that system worked better than I expected. The fan in the wall was a 1960’s exhaust fan like you would see above a stove. Chrome Nutone like the one pictured below.

I suppose you could have a heater and a small AC unit in one office and blow conditioned air through the wall.

 

[Smiles79]

Here is my input on that point.

Yes, I realize that you want to have just one unit to heat and cool both spaces. My earlier suggestions were ideas to try to change your mind and provide individual control and save on energy costs. But it’s your place and of course you can do what you want,
A friend of mine bought an old rustic house that was heated by a wood stove In the kitchen. It had a through the wall electric fan to blow some of the heat into an adjacent room. The door between the rooms had a big gap to provide return air. Once the wood stove was going strong and the kitchen was warm, that system worked better than I expected. The fan in the wall was a 1960’s exhaust fan like you would see above a stove. Chrome Nutone.

I suppose you could have a heater and a small AC unit in one office and blow conditioned air through the wall.

Got it, didn't mean to be rude. Thank you!

 

[Shiftless]

I don’t think you were anything close to rude. You asked an honest question and along with a few others, gave you some suggestions. I live in a very mild climate so I can’t speak from long term personal experience… just from what I’ve seen and heard of others doing to heat and cool.
It‘s nearly November and we have yet to turn on the furnace. Our 70 year old house varies between lower to upper 60’s this time of year.

 

[Smiles79]

Lucky, I've had the heat on in the house for almost a month!