The importance of having good seams
A tightly sealed duct system will not leak conditioned
air during the heating or cooling mode between the air handling
unit and the grilles and registers.
Conditioned
air delivered by a building air duct system will range in temperature
based on the Thermostat setting. If the
Thermostat setting on a properly designed air
conditioning system is set at 75 degrees F the
conditioned air in the cooling mode will range from 45
degrees F at the face of the evaporator coil to 80 degrees F at
the return air plenum. A five to six degree rise
in temperature is typical.
In the heating mode the discharge air at the heat
exchanger will average 160 degrees F for a
fossil fueled systems and 110 degrees F for an
electrically fueled system with return air temperature
at the return plenum averaging 65 degrees F.
Duct
pressures range from .5 inches water gage to 10 inches water
gage.
Today typical residential duct systems operate at
.5 inches, commercial duct systems operate at
1 inch, while high pressure industrial duct systems
operate between 4 to 6 inches.
Exposure of Temperature and
Pressure in HVAC Systems