✔What about the cold winters?
Our hot tubs are invented in and designed for the cold temperatures we know and are a custom to here in Slovenia and it and our hot tubs work well in very cold climates.
How you deal with a wood-fired hot tub in very cold weather depends on your usage pattern and whether or not electricity is available.
✅ If you are using it at least once a week you should be fine in all except the most extreme weather as the water (with appropriate covers) shouldn’t lose more than about 15-18 degrees per day in all except the most extreme weather. You do, however, want to avoid having the entire tub freeze solid as that will most likely damage the bottom boards.
✅If you will be leaving your tub untended for extended periods of time in sub-freezing weather, here are some things you can do to prevent damage to the tub from freezing:
✅If water availability is not an issue, drain all but 10cm or so and just let that freeze and refill when you return. The few inches of ice won’t hurt the tub and will help keep the tub bottom and base of the staves (the walls of the tub) “seasoned”. When you are ready to use the tub simply top it off and fire up the stove.
✅If water to refill the tub is an issue you can anchor 2-4 floating empty plastic milk jugs at varying levels in the tub. When the water freezes and expands the milk jugs will act as shock absorbers so the tub isn’t damaged. This approach is most useful when water to refill the tub is a problem.
✅If you do not drain the tub and notice a few inches of ice on the tub surface, just start up a small fire, and let the stove heat slowly. You can allow several inches of ice to form on the surface of the tub without doing any damage.
✅If the tub does happen to freeze completely, caution is advised. You can melt the ice by starting a fire, but a fast burning fire quickly melts the ice around the stove. The water can then boil away exposing the stove to air which will cause the aluminum to melt. Without water surrounding the stove it could melt. We recommend adding some water to the top of the frozen surface while melting the ice. You should try and heat your tub up at least once a week, and of course, heating it up means you get to enjoy it, too.
✅Some owners with tubs at cabins where there is no water available during winter months leave their tubs full, but secure with a rope a large, partially inflated inner tube to the bottom of the tub. This allows the inner tube to take the stress of the expanding ice so that the tub is not damaged. (The inner tube needs to be completely submerged at the bottom of the tub).
➡More info: https://en.lesenekadi.si/wood-fired-hot-tubs/