• No interior room is lost, compared to submersible heaters which take up the room of 2 people.
• An aluminum heater requires a minimum water volume.
• Allows for a marine grade vinyl insulating cover to be used thus retaining heat much better over a weekend (4 inches thick with child locks).
• The water stays cleaner, as wood is not being loaded inside the tub.
• You have better temperature control, using a high and low speed draft control to regulate the heating rate.
• Vented smoke-outlet for secondary combustion provides less smoke and sparks.
• Automatically circulates the water using thermosiphon (no electricity required).

All tub kits come complete with materials and hardware.

Chofu Wood-Fired Water Heater

The wood fired tub system is very inexpensive to operate (just the cost of wood). It is ideal in cottage country, where typically users enjoy the pleasures of a soak during weekends and holidays. Wood fired heating systems release considerable amounts of heat. The draw back of the Chofu system is that it must be drained and filled more often unless a optional 120VAC filter/pump system is added.

This model is a precision built wood-burning water heater designed specifically for hot tubs. It circulates water using the principal of thermosiphon (the pumping action created by rising hot water), eliminating the need for a circulating pump or electricity. This unique feature opens up a whole new range of possibilities for alternative hot tubs. Now you can have a basic soaking tub without pumps, chemicals, or high maintenance.

The stove body of the Chofu is made with high quality stainless steel so it can be used outside, without worry. And since the firebox is also made of stainless steel it will withstand years of service without danger of burning-out. The smoke outlet on the Chofu features a unique vented collar that provides secondary combustion of unburned gases, for reducing smoke emissions and chimney sparks.

The Chofu utilizes a sophisticated heat exchange design for efficient water heating. The stainless steel stove body surrounding the firebox is a double-walled water-jacket with a 1-inch space between, making the entire firebox (except the front) a heat-transferring surface. Additional heat transfer takes place in a water-filled baffle plate that runs horizontally through the firebox. The baffle deflects the path of the fire, so it gives up more heat into the water jacket before going up the chimney.

Chofu Propane Water Heater

The Chofu Propane Heater is a high efficiency water heater designed specifically for hot tubs. Like the Chofu Wood-Fired, the Propane Heater circulates water by thermosiphon (the pumping action created by rising hot water, eliminating the need for a circulating pump or electricity. This revolutionary concept enables you to have a simple soaking tub without jets, chemicals, etc.

The Chofu Propane Heater greatly reduces hot tub maintenance, since it has no moving parts and requires no electricity. It's designed for outdoor use, with a durable powder coated steel outer casing and a stainless steel exhaust cowling.

Inside the Chofu is an elaborate network of copper tubes with heat collecting fins, that are heated by six stainless steel burners. The configuration of the copper tubes is designed to create thermosiphon circulation by allowing the heated water inside the heater to rise up and flow into the tub.