Newmac BC 160, Installation, Operating And Service Manual

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Chemical chimney cleaners are available. Opinions on their effectiveness vary, but apparently when used regularly,
and as directed, they work, and do not damage chimneys. The usual chimney-cleaning method is the oldest human
energy and some kind of mechanical tool. A stiff wire brush, a heavy chain (perhaps in a bag) hung with a rope and
worked up and down from the top of the chimney, and very small brushes have all been used. Professional chimney
sweeps are also reappearing.
Some people clean yearly, others after every few cords of wood burned, but there are so many factors influencing
creosote build up that such generalizations are not appropriate in most particular cases. In new installations, or when
changes occur (such as a different stove) the chimney should be checked frequently (after 2 weeks, then after a
month, then after another 2 month, etc.) until it is clear how frequently cleaning is needed.
The preceding is an excerpt from “THE WOODBURNERS ENCYCLOPEDIA” published by Vermont Crossroads Press, Inc. – December 1976.
WOOD IS A SAFE, CLEAN AND ECONOMICAL FUEL
Species
Approx. Wt.
Per Cord
BTU Per Air
Dried Cord
Equivalent Value #2
Heating Oil In Litres
Cost at
$0.25
Cost at
$0.30
Cost at
$0.35
Hickory 3595 30,600,000 827.4 $206.85 $248.22 $289.59
Hard Maple 3075 29,000,000 784.6 196.15 235.38 274.61
Beech 3240 27,800,000 752.4 188.10 225.72 263.34
Red Oak 3240 27,300,000 738.7 184.67 221.61 258.54
Yellow Birch 3000 26,200,000 709.2 177.30 212.76 248.22
Elm 2750 24,500,000 662.8 165.70 198.84 231.98
Soft Maple 2500 24,000,000 649.2 162.30 194.76 227.22
Tamarack 2500 24,000,000 649.2 162.30 194.76 227.22
Cherry 2550 23,500,000 635.5 158.87 190.65 222.42
Ash 2950 22,600,000 611.4 152.85 183.42 213.99
Spruce 2100 18,100,000 490.1 122.52 147.03 171.53
Hemlock 2100 17,900,000 484.1 121.02 145.23 169.43
Aspen 1900 17,700,000 483.2 120.80 144.96 169.12
White Pine 1800 17,700,000 462.8 115.70 138.84 161.98
Basswood 1900 17,000,000 459.6 114.90 137.88 160.86
To change litres (l) to US gal. Multiply by .264
For the least amount of wood handling, the wood with the highest heat content is most desirable.
An open fireplace can actually refrigerate a house because it sucks in so much cold air which is only partially used for
combustion. A carefully designed fireplace makes use of perhaps 10-15% of the heat available; most still going up
the flue. The well constructed potbellies get perhaps 20-25% and the automatic, draft regulated, tightly sealed wood
heaters get perhaps 50%.
Notice that the percentage efficiency goes up as the combustion process becomes more and more controlled. The
roaring fire is a complete waste of fuel. The best situation is one where the combustion chamber if gas-tight. This
allows a controlled fire that toasts the wood and puts the right quality of wood gas in the right place and at the right
temperature for optimal combustion and heat transfer.
THE NEWMAC COMBINATION OIL AND WOOD FURNACE toasts the wood to charcoal and the charcoal burns to
dust leaving a minute amount of residue. From the above heat values, it can be seen that a cord of Hickory wood is
equivalent to $248.22 (@ $0.30 per litre) worth of oil, over twice as much as you would pay for a cord of wood.
Without taking into account all the free wood that is available, EFFICIENT WOOD HEATING cuts your heating costs
in half.