Heating Water with Wood
If you are off-grid and living in a wooded area, wood fuel can be inexpensive and readily available. You may already be heating and cooking with wood. Lets look at products and methods of heating water with wood.
Like all things off-grid, you will be intimately involved in the process of creating your own hot water.
Compared to conventional housing and appliances, heating water with wood is time consuming and inefficient. Rarely will the water be hot when you want it, so you need to plan at least an hour ahead (for a 10 gallon tank) to get the fire going and keep it going.
Wood-Fired Water Heaters
You can make a heater using a 55-gallon barrel like the one shown here, or you can buy a professional stainless steel boiler like the three shown below.
The builder of the 55-gallon drum heater installed a coil of copper tubing for the heat transfer and bought a door kit for the end of the barrel.
See the details of making this wood-fired boiler on this page: DIY Wood Fired Hot Tubs
Timberline Stainless Steel Boiler
These stainless steel boilers will last a lot longer than a 55-gallon barrel, but they’re expensive ($2,252.63* on EBay). This 100% stainless steel water boiler produces about 55,000 BTU of heating capacity by only using wood. That’s enough to heat 200 hundred gallons in about four hours. There are three sizes.
The dimensions of the TimberLine Blaze Stoves are 19″ wide x 29 1/2″ long x 22″ high with at total weight of 50 lbs. The fire box can accommodates 28″ logs. The Blaze Water Stove comes with a 3/4″ drain plug to completely drain the internal water jacket, preventing any damage that could be caused by freezing. Also included are a temperature gauge to regulate the hot water and a safety pressure valve.
You’ll need to add an insulated water storage tank to complete this wood-fired water heater.
Hot Water System Two from Lehman’s
This sturdy wood-fired water heater is made entirely of strong, 3/16″ thick welded steel. It holds 15 gallons of water.
Water completely surrounds a 2.4 cu/ft firebox, so all the heat goes toward heating the contents.
The dimensions are: 24″Hx20″Wx34″L, 235 lbs. and can burn up to 26″ logs. It requires a 6″ flue. There is a draft control on the door.
Click on image to see details at Lehman’s. $1,609.00* plus $299.00* shipping.
This wood-fired water heater is exempt from EPA regulations and is legal for sale in most of the USA; however, it’s best to check your state’s regulations before purchase. This model is not legal for sale in the state of Washington.
Already Using a Wood Stove for Heating and Cooking? Why Not Add a Water Heating Option as Well?
The designers cleverly added a hot water tank for their wood stove that just clips on. You can use two tanks heating up to 10 gallons of water.
The Steelhead Mini Wood Stove
This well-built wood stove will output between 10K and 23K BTU and is enough to heat 1000 sq./ft. Up to 18” log capability with burn times up to 8 hours. Beat of all, it has an outside air vent for combustion air so it won’t freeze distant areas of your home.
See more of our favorite tiny wood stoves on this page of the Tiny Life Consulting website: Wood Stoves for Tiny Abodes
The Cubic Mini Wood Stove also has a water tank addition.
Elmira Fireview Wood Cookstove with Water Heating Option
This Elmira Fireview Wood Cookstove has an optional built-in water jacket so you can heat your house, cook your food, and heat your water all at the same time.
It’s a well thought-out product.
“The Elmira Fireview Wood Cookstove brings the old-world coziness of the fire and the modern convenience of gas cooking into your kitchen. Choose the features that suit your needs: enjoy the incomparable warmth and pleasure of wood cooking; make meals faster and keep your kitchen cooler on hot summer days with optional high-output gas burners; or, extend your prep area with the optional work surface. A large viewing window (standard on every Fireview stove) lets you enjoy the dramatic display of the fire while quickly and easily fine-tuning the flame for perfect cooking temperatures every time.”
There are three models to choose from with several options like gas burners. It’s airtight with an outside air vent to draw plenty of air into the firebox without having to pull air from the room. The 21′ firebox will accommodate 18″ logs. The oven is a spacious 3 cu. ft.
Because the Elmira Fireview Wood Cookstove is primarily designed as a cooking appliance, it is exempt from EPA regulations.
Elmira Water-Jacket-Manual-2013
Click on image to download complete .pdf instructions.
Plumbing Diagram
There are detailed instructions about the plumbing needed to use the water jacket to heat water.
For the thermosyphon to work properly, the water tank needs to be one foot higher for every two feet away from the heat source.
Be careful if you’re doing this yourself! A hot water system can explode with life-threatening consequences if not installed properly. You must use correctly rated and properly drained and located pressure temperature relief valves.
Wood-heated hot water systems produce scalding hot water and steam. Be sure your system includes
an operational and properly-installed tempering valve.
Adding water-heating ability to your wood stove
You can add a stainless steel hot water heating coil to your wood stove using this kit available from EBay.
It’s installed directly in the firebox, either on the side or the top. The coil measures 15″, by 20″.
Click on image to see details and other options. Cost ranges from $255.00 to $379.00* (plus as much as $70.75* shipping). They’ll include the correct hole saw for another $15.00.
Heated Water Holding Tank
Once you have your boiler, you need a holding tank. Your holding tank needs to be strong enough to handle the pressure of the hot water, and well-insulated to keep your warmed water hot for as long as possible.
The Mega-Stor is a stainless-steel indirect water heater which stores abundant domestic hot water utilizing energy provided by your boiler. With a stainless steel, smooth surface coil that transfers heat throughout the tank, the Mega-Stor is capable of recovery rates well in excess of a typical gas, electric or oil water heater. The two-inch thick layer of polystyrene foam insulation keeps the water in your Mega-Stor hot for hours during stand-by periods. The Mega-Stor is also equipped with a removable cover for ease of inspection. Mega-Stor has a limited lifetime warranty. Capacity is 40 gallons.
Crown has several sizes of water holding tanks from 20 to 119 gallons, but they’re pricey. Click on image to see details.
Portable Wood Burner Water Heater | Fits Stoves with 4 Inch Flue
Here’s a unique water heater that fits around the flue of your tiny wood stove. It only holds 5 liters of water and comes from the UK. It sells for about $121.22*. Shipping is as much as $141.63.*
That’s enough for drinking and washing dishes, but not showering or bathing. It’s pretty much the same as a big kettle, but keeps the cooking surface of your wood stove clear for other pots and pans. Click on image to see more.
For More Information About Wood-Fired Water Heaters, Visit My Pinterest Board
Water heater attached to wood stove from Humble Homes
More pages of this website you’ll be interested in:
Living Off-Grid In A Tiny House
Every hot water heater installation must include a pressure relief valve like this one.
Failure to install one could result in a explosive rupture of the pipes or tank and could result in serious damage and injury.