MIL-HDBK-1003/3
This section does not apply to industrial ventilation
systems, e.g., systems to control fumes, vapors, and dust from
such processes as plating, painting, welding, and woodworking.
Refer to the MIL-HDBK-1003/17 and ASHRAE Handbook, HVAC Systems
and Applications, for guidance on design of these systems. The
EFD or EFA and the Naval Facilities Engineering Service Center
(NFESC) can provide additional assistance.
5.2.3
Total Heating Load. Sum the transmission loads with
infiltration and ventilation loads to get the total heating load.
To this computed total heating load, add the following to size
central equipment (do not apply these factors when sizing
terminal equipment such a finned-tube radiation, fan-coil units,
etc.):
a)
Exposure factor (prevailing wind side) up to 15
percent.
b) Pickup (for intermittently heated buildings with
primary heat sources such as boilers, steam-to-water heat
exchangers, etc.) 10 percent.
c) Buildings with night setback. A residence with 10
degrees F setback requires 30 percent oversizing for acceptance
pickup and minimum energy requirements.
5.3
Cooling Load. Computation of the peak cooling load can
be a difficult effort. Heat gain is composed of or influenced by
the conduction heat gain through opaque portions of the building
skin; the conduction plus solar radiation through windows and
skylights; the building internal loads such as people, lights,
equipment, motors, appliances, and devices; and outdoor air load
from infiltration. For sizing VAV systems, calculation of loads
has more stringent requirements. Refer to Appendix C.
5.3.1
Transmission
5.3.1.1
Walls and Roof
EQUATION:
Q = U * A * (To - Ti)
(3)
Refer to par. 5.2.1 for definition of terms.
5.3.1.2
Glass
a)
Transmission
EQUATION:
Q = U * A * (To - Ti)
(4)
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