Troubleshooting guide

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The major product from burning wood is:
1) Heat. Since there is not 100% combustion of the wood pellet, there are two by-products, plus
water, from burning pellets. These are:
* Carbon monoxide and unburned gases (Exhaust gases)
* Ash
St. Croix stoves are designed to effectively handle the elimination of the by-products of
combustion.
St. Croix stoves are engineered to transfer a designed amount of the heat produced into the area
around the stove. Exhaust temperatures may vary from approximately 200°F to 450°F.
Ash & Clinkers
In addition to gases and carbon, wood contains various minerals. After the gases and carbon
burns these minerals remain and are referred to as "ash".
Most ash will be blown out of the burn grate and settle in the ash pan. Ash that is very light may
travel along with the exhaust gases. This ash is called "fly ash". It often settles in various areas of
the stove and exhaust pipe. Improper cleaning of fly ash will result in restriction of combustion
air. The results are a poor burning fire.
Some ash is heavy enough to remain in the burn grate unless it is removed with high air velocity
or through mechanical means. If attempts are made to remove all ash with air velocity alone, the
air to fuel ratio will be out of balance. When this happens pellets may be blown out of the burn
grate and the efficiency of burn will be lowered.
When ash is exposed to temperatures that exceed the melting point of the ash, for long enough
time, "CLINKERS" will form. Clinkers cannot be removed with air velocity. They quickly shut
off primary combustion air and smother the fire.
St. Croix’s Versa Grate System" helps in the removal of ash from the burn grate. The self-
cleaning grate helps to minimize clinkering, but will not eliminate all clinkers and helps in
removing ash from the burn grate. The Versa Grate System should be used with pellets that meet
or exceed the PFI's "Premium" pellet fuel quality standards. Many Standard Grade pellets will
not work in Residential pellet heating appliances.
Assessing Pellet Quality
Pellets are an important component of a residential wood pellet heating system.
A complete residential wood pellet heating system consists of 1) the pellet stove, 2) the
installation, 3) the fuel, 4) operation and maintenance. When any one of these factors does not
meet required specifications, the operation of the stove will be compromised.
Pellets, however, are often the least understood and most often ignored component in
DIAGNOSING a pellet stove.