Country Lore: Wood-Fired Hot Tub

The author describes how he built his own wood-fueled hot tub.
December/January 2005
http://www.motherearthnews.com/diy/country-lore-wood-fired-hot-tub-zmaz05djzsel.aspx
Wood-fired hot tubs are a novel way to enjoy this luxury.


Photo courtesy Angus W. Stocking

The four-acre parcel we bought near Paonia, Colo., was perfect for starting a small farm, but the existing residence, a small A-frame, was missing a few amenities: room for a washer and dryer, and even worse — a bathtub! We saw an advertisement for the Chofu (www.islandhottub.com), a wood-fired water heater that seemed like what we needed. Because the Chofu is free-standing, it can be hooked up to just about anything that can hold water, so we thought an old stock tank would work.

We took the plunge and ordered. A week later, UPS dropped off two boxes in our driveway — the surprisingly light Chofu and a separate box containing four 2-foot sections of stainless steel stovepipe.

Assembly took an afternoon and was fairly easy. Here are some tips from our experience: The hardest part was assembling the stovepipe. Because the stovepipe is stainless steel, it comes with a cobalt drill bit. It is a two-person assembly job, and you’ll need a drill, heavy pliers and gloves — the pipe sections had some sharp edges. The stove itself was fully assembled and just needed to be connected to the “tub.” The hole through the stock tank (or whatever you use) doesn’t need to be perfect because rubber gaskets for waterproofing were included. There was a little leak where the tank connected to the stainless steel water pipe, but we fixed it by simply using better-quality hose clamps than the ones provided.

When assembled, the unit is rather striking. The design is well thought out and combines simplicity with efficiency. Water circulates by the thermo-siphon effect: Cold water comes in the lower inlet, is heated in a jacket surrounding the firebox and flows through the top outlet into the tank. The circulating water keeps the stove from getting too hot to touch. Best of all, it’s silent — no pumps, no bubbles and no furnace. In the winter, our little tank goes from nearly freezing water to a comfortable soaking temperature in less than one hour with just an armful of wood.

Soaking is wonderful! We sit with stars overhead, listening to the creek and to the wind in the trees. It beats a bathtub any day.