Trouble shooting
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GENERAL INFORMATION
BURNING SPEED:
The velocity at which flame travels through an air-gas mixture. Burning speeds vary with types of gases,
and the amount of air mixed with the gas. This air to gas ratio is very important in that it is directly
related to flame stability.
PRODUCTS OF COMBUSTION:
Carbon dioxide and water vapor is formed in burning plus the nitrogen in the reactants that entered with
the combustion air.
FLUE PRODUCTS:
The combination of combustion and excess air leaving the combustion area. Since water is produced as a
vapor in the burning of gas it is also present in flue products. If the flue products and vent system remain
hot enough this vapor is harmlessly discharged. If not, the vapor can reach the dew point and condense
into water which can accumulate in the system.
INCOMPLETE COMBUSTION:
A poorly vented appliance restricts flow of air into an appliance. Lack of ventilation around an appliance
may lower oxygen content in the surrounding air. This can be a result of spillage of combustion products
into the room as well. These conditions can cause incomplete combustion and poor performance of an
appliance. Adequate, but not excessive ventilation is a must and cannot be over emphasized.
PRIMARY AIR:
That air which is mixed with gas before the gas leaves the burner port to burn. Ideal burning condition
generally is 10 cubic feet of air per cubic foot of gas.
SECONDARY AIR:
The remaining air needed for complete combustion besides primary air. This is the air surrounding the
flames.
FLAME STABILITY:
Primary air, burning speed, port size and port depth are several factors affecting flame stability. Flames
on a burner tend to stabilize at a point where flow velocity out and burning speed back are equal. This
balance of flow velocities and burning speed explain why flames change when primary air or gas rate is
adjusted.
B.T.U.:
British Thermal Units is the heat energy produced when burning a fuel gas. One BTU of heat will raise the
temperature of one pound of fresh water one degree Fahrenheit.
