Draft Control - Field Controls SWG-3 Product Manual

DRAFT CONTROL

For proper operation and efficient fuel consumption in oil, gas, and/or coal-fired heating appliances, draft must remain
constant. When it is, combustion is more complete, fuels are utilized efficiently, and money is saved. Field Draft Controls
maintain consistent draft by counteracting the negative forces caused by changes in temperature and barometric pressure, as
well as the effects of wind.
*MADE WITH GALVANIZED STEEL.
HOW DRAFT CONTROLS WORK
Static pressure of the cool air Illustration A (1)
pressure on the outside of the furnace or boiler, the
breaching, and stack. The pressure difference between
the room air and heated gas (air) causes products of
combustion (2) to flow (draft) through the unit and rise
through the breach and chimney. Room temperature air
enters through the barometric draft control
amount needed to overcome the excess drafts caused by
temperature variations, wind fluctuations, and barometric
pressure changes. Combustion of fuel is complete and the
process is stabilized. The velocity of combustion gases
through the heat exchanger is slowed so more heat is
extracted. The unit operates more efficiently, reliably, and
requires less maintenance.
28
RC
M+MG2
exerts
(3)
(4)
in the precise
M
MG-1
ILLUSTRATION A
Gas Installation
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