Call our National Sales Team for more information! (800) 780-4302

Or contact Wood Heating Solutions at:

We carry 6 sizes of front loading
residential COAL boilers.

These models are specifically
designed to burn coal.

Our fan feeds oxygen in from the bottom
so the coal burns easily.
Shaker grates are installed in
all models to help get rid of the clinkers.


The Hyprotherm FLRH-85
is rated at 95,243 BTU
with a 85 gallon water tank.
Heats up to 2,300 sq ft.


The Hyprotherm FLRH-100
is rated at 112,050 BTU
with a 100 gallon water tank.
Heats up to 2,800 sq ft.


The Hyprotherm FLRH-185
is rated at 207,293 BTU
with a 185 gallon water tank.
Heats up to 5,182 sq ft.


The Hyprotherm FLRH-265
is rated at 296,933 BTU
with a 266 gallon water tank.
Heats up to 7,400 sq ft.


The Hyprotherm FLRH-300
is rated at 336,150 BTU
with a 301 gallon water tank.
Heats up to 8,400 sq ft.


The Hyprotherm FLRH-350
is rated at 392,175 BTU
with a 350 gallon water tank.
Heats up to 9,800 sq ft.


The Hyprotherm FLRH-400
is rated at 451,562 BTU
with a 403 gallon water tank.
Heats up to 11,288 sq ft.

Burning Coal

Many manufacturers changed to natural gas
in making their products but are now switching
back to coal because it is less expensive.

outdoor coal furnace

Coal burns super hot and needs
high quality mild steel – like ours;
one of the few that can withstand the intense heat.

The Hyprotherm Outdoor Coal Furnace is specifically designed to
burn coal and it comes with a coal shaker grate to help get rid of clinkers.

Hyprotherm Coal Firebox
Hyprotherm Coal Shaker Grate Handle
Hyprotherm Coal Shaker Grate

Click on the pictures to see a LARGER image.

A video of how the shaker grate works.

Grades of Coal

Anthracite – this type of coal has the highest percentage of fixed carbon and a lower percentage of volatile material than all other coals, making it harder to ignite. However, when it is ignited, it burns relatively smokeless.The most well-known anthracite mines in the United States are in eastern Pennsylvania.

We offer Anthracite Coal (1.75″ to 3″)
that is stove-egg size for sale.

There are 50 bags per pallet,
and each bag weighs 40 lbs.

This coal is cleaned coal
and does not need to be removed from the bag
before being put in the coal boiler.

Each bag costs $8.00,
so each pallet costs $400.00.

Each pallet weighs 2,100 lbs
and the pallets are 40″ x 48″ x 48″

Bituminous – Bituminous coal is the most abundant and most widely used coal. This is the type of coal found in the Appalachian region. It has a higher heating potential and is used for making coke. It has a higher percentage of fixed carbon, greater heat value and better weathering characteristics than lignite and sub-lignite coals.Most of the non-metallurgical grades of bituminous coal are burned in boilers or furnaces to obtain thermal energy for generating electricity. Because bituminous coal is softer than anthracite, it is often referred to as soft coal.  It does emit smoke as it burns, unlike anthracite.

However, there is a region in Southern West Virginia where the bituminous coal burns relatively smokeless. The Smokeless Coal Fields of Southern West Virginia are unique in the world.

Sub-bituminous – A lesser grade of coal, it has more moisture and less carbon than bituminous.  Nut Coal – Very small coal – about 1/4″ in size. See important note below.

nut coalrice coalpea stoker coal

left picture – nut coal
middle picture – rice coal
right picture – pea coal

You must notify us, if you plan on using “NUT COAL”, rice coal or pea coal, as they are all very small.

You cannot burn “run of the mine” coal, without voiding the warranty
because it burns way too hot.

In the United States, the coal power plants
generate 50% of the electricity produced.
Buy a Coal Burning Furnace TODAY!

  • Lower your utility bills! Coal is easy to load – by the shovel load, as opposed to wood. You can eliminate your gas, electric or oil bill simply by using a Hyprotherm Outdoor Wood Coal Furnace to heat your home and hot water. Coal is very plentiful in many Eastern states.

  • Heating with coal – outside of the house – is CLEANER!

  • No more smoke, ashes, bark, bugs, log piles and trash in the house. Many types of coal burn virtually smokeless.
    Heat your hot water with your Hyprotherm Furnace and save $30-60 a month on this feature alone! It takes care of all your hot water needs and the elements in your hot water heater may never come on again!

  • Safety. Our furnace is made to be situated away from the house, in the yard. The usual distance is about 50 to 100 feet. Outdoor coal furnaces remove the danger of wood stove fires in the house. Any fire department that compares the safety of indoor units versus outdoor furnaces will clearly state that outdoor furnaces are the winners. This safety feature usually lowers your insurance rates.With ZERO wires, electronics, fans and controls on the outside of our furnaces, our unit is simpler and safer.

  • One furnace can heat multiple buildings; so there is no need to purchase a heat source for each. Simply run an extra run of PEX pipe to the area you want to heat – even garages, shops and greenhouses without an existing furnace! Some people even heat their driveways!

  • Residential and commercial buildings, factories, restaurants and garages can all be heated easily with our residential coal boilers.
    Simple, clean and efficient, one outdoor wood coal boiler can heat your house or/and shop, garage, swimming pool, hot tub, greenhouse or factory.*

The Standard Insulation Package on our furnaces is:

Three inches of Knauf ET Blanket = R- 11.5 + One quarter inch Solar Guard = R- 11.6 on side walls for a standard insulation of R- 23.10

Two inches of Morgan Super Wool Blanket on front of furnace and in the door for a standard insulation of R- 56.80

If you want the best insulated furnace in the industry, we offer a Cold Weather Package for an additional $325.00.

This amazing package covers the entire furnace in Morgan Super Wool instead of Knauf ET. The Cold Weather Package on our Hyprotherm furnaces is:

Two inches of Morgan Super Wool Blanket = R- 56.80 + One quarter inch Solar Guard = R- 11.60 for a Cold Weather Package R-value of 68.40

Three inches of Morgan Super Wool Blanket on front of furnace and in the door for a Cold Weather Package R-value of 88.23

You can actually put your hand under Morgan Super Wool, heat the other side of it with a blow torch and not burn your hand!  Don’t believe us? Find that video and more insulation information by going to the insulation page.

Hyprotherm offers a firebox upgrade from 3/8″ to 1/2″ for $650.00. This will help increase the life of your boiler. You can also upgrade your water jacket to 1/4″ for $450.00 to give you many additional years as well.

Hydronic Installation Manual