Outdoor Wood Burning Furnace

BTU Load Calculator     

The easiest and best way to establish your BTU requirement
is to look at your current furnace.

There is normally a label on the furnace that tells you the BTU output.
If your furnace is 90% efficient, you may have to multiply that amount by 0.90.
If there isn't as label affixed, call the manufacturer or go to their website with your
model number and they will tell you the rating. 

Any furnace rated at 180,000 BTU NET output or less, can be generally be
replaced with our NCB-120, assuming that it heats your home well now.

Of course if a furnace is oversized (e.g 100,000) and can really heat your home with 80,000 BTU, then that should be considered. Use square footage estimates below. 

Doubling the furnaces output (buying a bigger model) has great benefits to you,
like loading less often!

There is no negative to getting a bigger furnace because it is not like purchasing
an air conditioner where if you get one too big, it becomes inefficient.
It is simply like getting a bigger fuel tank or propane tank,
so that it will hold more fuel and you will need to fill it less often.

I got one size bigger for my home and I only load it once a day, instead of twice
(normally once in the morning and once at night)

The NCB-120 STORES 120,000 BTU, ready for use, unlike others who give you
phony numbers of what a furnace can do at maximum output, which may be 20 minutes.

Also remember, that the home should be no bigger than the rated square footage
unless in a southern climate like us in AR or in NC or further south.

See listings HERE

But remember, it is more critical to have a heat exchanger with the correct output. 
If the heat exchanger is too small, you will never get enough heat,
no matter how big the furnace is!

Select or input information on the first 4 lines
and then hit button to Calculate BTU

Select Insulation Type
Select Climate/Region
Square footage to heat x
Ceiling height (feet)
===>   BTU     (Watts )

Which furnace do YOU need?

Our standard and least expensive boiler, is the the NCB-120 furnace, which is
160,000 REAL BTU - no funny math here!

The NCB-175 is 220,000 BTU

The NCB-250 is 300,000 BTU

The NCB-275G is 380,000 BTU

The NCB-325G is 460,000 BTU

The NCB-400G is 500,000 BTU

The EPA White Tag GT-6000 is 250,000 BTU

Nature's Comfort NCB-175


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Our standard furnace and least expensive furnace (the NCB-120) easily will heat 3,000 sq feet
including all buildings, well insulated.

We have models that will heat up to 12,000 sq. ft!

In Southern climates like NC, SC, GA, TN, AL, MS, TX
it can often heat more and still only have to load it once in the morning and once in the evening, at the most.