Considering Ventless or Infrared Heaters -- How do you heat your shack?

[Polish Wizard]

My sugar shack is a 10x10 addition at the back of a roughly 16x16 old pony barn.
The structure was made with Amish rough-cut lumber, and has spaces between each of the exterior boards that I assume was designed to allow fresh air for the animals -- so obviously not draft free.

For my own comfort I'd like to add some type of heat -- like propane ventless heater or infrared system.

I plan on buying a new arch/evaporator next year, and that should be very efficient and not allowing heat to escape other than via steam rising through the open cupola.
An additional benefit of a shack heating system would be keeping stored sap from freezing, as well as aid in operating an anticipated RO Bucket.

With my on-line research I noticed ventless propane heaters have been used in ice fishing shacks.
While I have electric available in the barn I don't believe these ventless heaters have a fan included for circulating heat.
I don't know if the separation of the arch from the rest of the barn will make an infrared system workable.

I'd rather not consider a wood stove because it would eat up too much space while maintaining clearances to combustibles, and I'd rather not use my cut wood for that purpose.

How do you folks provide heat to your shacks?
I'd love to hear any experiences or ideas -- both good and bad results, and how you think my structure layout may impact your suggestions.

[Masnart]

Doesn't the ambient air temperature make a difference in evaporation rate? I was kicked out of the house for setting off CO detectors while boiling and found it's a faster boil out in the cold with a hot burner/rolling boil.

[Pdiamond]

Is there a way you can place a board over the openings to cover them. that will conserve some of your heat. The heaters in ice shanties do not have fans as far as I know. I have a 12 x 16 sugar house and it takes a little while to warm up and I don't have any open spaces.

[Polish Wizard]

Is there a way you can place a board over the openings to cover them.

I believe what you are describing is called board and batten where thinner strips are installed to cover the void space between the vertical wall boards.
You'll see many of the folks on this site have posted pictures of their sugar houses built in this style.
While it's certainly possible it hasn't been my first plan of action.
I'm not expecting to work in my T-shirt, but it would be nice to have a way to help bring up the temps and maybe defrost my sap storage barrel if and when it freezes -- especially at the bottom where the drain valve is installed on the side of the 55-gallon drum.

[VTnewguy]

If you have electric, how about a electric torpedo heater? I wouldn't be too worried about frozen sap in a tank. If it's that cold the sap isn't running anyhow.

[MISugarDaddy]

When we built our current sugarhouse in 2013, we installed a ventless heater to keep temps above freezing at night. Our heater had a fan to circulate the heat. The problem we had with the heater was that it caused a considerable amount of condensation in the sugarhouse as it was tightly built and insulated. We have since replaced the heater with a vented heater that has a fan and have eliminated the condensation problem when the sugarhouse is closed up at night. In fact, the vented heater helps to eliminate humidity in the sugarhouse when it is closed up.
Gary

[maple flats]

I have a 16x24 board and batten sugarhouse, but about 1/4 of the batten are not on yet. Also, I'd need to seal up spaces at the top plate. On the gable ends there is a 1" space between each 1x8 purlin, then another space, on the other walls there is a 2" space, between the trusses (every 2'). In addition I have just steel on the purlins, no plywood so I get loads of heat loss. When boiling that is not an issue, it gets warm enough but not hot in there unless the outside temp climbs to 65F or higher. I only heat my RO storage closet.
That being said, if you get Infrared heaters, aimed down I think you will feel warm. I've been in large warehouses with such heating and it's surprising how warm it feels. Those heaters don't heat the air, just solid surfaces (and you).

[18mile]

I have used ventless and also have condensation. For the little amount of time I need it there is no major problem. I mostly worry about freezing the ro

[TapTapTap]

I wouldn't be too worried about frozen sap in a tank. If it's that cold the sap isn't running anyhow.

I agree that shouldn't be a concern. For a heater do an IR. And cover up those gaps with batten boards. Most anything else would be a waste, especially if it's windy out.

[VT_K9]

If you don't want to batten the outside of the building you could put up strips on the inside to help keep heat in the area where you are. We did that in the old sugarhouse. When we put the RO area in we had a trash can style propane heater to help. Did not do much for circulation but it helped.

In the new sugarhouse we changed over to oil....never would have thought how cold it got inside. Not to mention a very large concrete floor. We installed a modine style propane heater. Definitely could have gone larger. We put it where the majority of the work is done on the evaporator. Without a doubt it make a difference in our comfort and I think it may improve the evaporator's performance a smidgeon. Maybe not but it helps in my mind. We build and insulated an RO room. We use a vented propane heater. I did not want to rely on a sensor failure to shut down the heater if O2 got too low or a failure of the sensor because it just went bad and a fail safe would stop the heater from working. I prefer and would recommend a vented heater for a good installation. In an ice shanty or small space a smaller propane/electric honey comb type heater would be nice.

Mike