Hot tub with built in wood stove heater?

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Don2222

Minister of Fire
Hearth Supporter
Feb 1, 2010
9,149
Salem NH
Hello
Just came across this wood fired hot tub. Takes about 1.5 hours to warm up!
Does anyone have one? Is it worth it?
Nice install video.

Looks like about $5k !!
https://www.redwoodoutdoors.com/pro...ot-tub-internal-stove-5-person/?sku=HT-INT-5L

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Snorkel tubs pop up every once and a while here. The value depends on the owner's personal time to keep it get it up to temp and keep it clean.
 
Yeah they're around. A local snowmobile club has one at their cabin. Beautiful place right in the middle of the mountains, 60 miles from the nearest road. They fill it from a stream that runs year round. It has 2 heaters, a built in wood fired heater, and an external heater that is essentially a homemade wood stove with water tubes and a pump.
 
My cousins have one and they love it. Personally it seems to me like it would be hard to maintain the right temperature with it being wood fired but maybe I don't know how it works.
 
I BUILT ONE!!! It's an 8'x8', cinder block, concrete floor, painted with pool epoxy paint, complete with skimmer, pump and sand filter. My cousin welded me a homemade version of a snorkel stove (aluminum) and it worked... "great". I say "great" and not GREAT! because there are some issues:

1. I didn't account for the stove floating and I have no way to attach it to the tub. I ended up constructing a table with 20 gallons of concrete in the base to tie the stove down to. Worked fine but all the "fixtures" to attach the stove to the table are not aluminum. These points created rust and rust is hard to deal with in a hot tub.

2. Takes a while to heat up. 880 gallons of water with the snorkel stove AND a "bubble thermal cover" takes about 8 hours to go from 45 degree water to 100 degree water. This pretty much means it's a Saturday only heater. I work in my shop on Saturdays so when I go out early and build a fire in my shop, I would also build a fire in my snorkel heater. That evening it was nice!

3. Just an FYI, it's true what you read. You need to circulate the water to heat it up. I would burn my heater for 3 hours and the water around the stove would be great. The heat would never transfer further away from the heater until I turned the pump on.

In the end, I've taken the snorkel heater out permanently and we use the 8'x8' tub as a "dipping pool" in the summer. Works great.
That being said, I'm investigating getting a stock tank, putting a coil stove underground (I live on a slope), putting the tank on top and filling up the area around the coil with gravel. The coil will be in a bricked up area to build a fire in but the gravel all around will allow (hopefully) for radiant heat traveling up. Maybe the coil can heat the water and the heat transfer from the gravel can help retain the heat. Anyone have any thoughts on that?
 
i have build them and just used a old wood stove and copper coil wrapped around the stove pipe and water flow circulating back to the tub.. way easier to control temp that way.