06-06
with modular heat pumps each unit shall have an individual
control.
a. Perimeter rooms (other than corner rooms) on the same exposure,
and in a group not exceeding four.
b. Interior offices: Based on the architectural layout, as many as
six offices can be grouped together as one temperature control
zone.
5. Limitations:
a. The interior and perimeter spaces shall not be grouped together
to form one temperature control unit.
b. Areas on different exposures.
c. Corridors and occupied (perimeter or interior) areas.
B. FAN VOLUMETRIC CONTROLS: For fan volumetric controls of the VAV
(variable air volume systems), the following guidelines shall apply:
1. Variable Speed Drive Package: For air handling units of 280 m3/min
(10,000 CFM) and larger capacities, the package of the volumetric
controls shall consist of the variable speed drives for the supply
and return air fans and the control accessories comprising of the
air flow measuring devices and static pressure sensor(s). The
preferred sequence of operation is described in VA Standard Detail
No. 15900-11.
2. Constant Speed Operation: For air handling units smaller than 280
m3/min (10,000 CFM) capacity, the individual room temperature
control shall involve variation in the supply air volume. However,
the supply and return air fans shall continue to operate at
constant speed. During part load conditions, the bypass type of
room air terminal units will divert (and relieve) the supply air
into the ceiling air plenum, where, after mixing with the room
return air, it will find its way into the return air system.
C. HEATING CONTROLS: See Article 4.
D. COOLING CONTROLS: See Article 5.
3.5 SMOKE AND FIRE CONTROL
The smoke control for the HVAC systems shall be designed in accordance
with NFPA 90A to affect system shutdown in the event of smoke
detection. The systems shall be incorporated with the following
features:
A. SMOKE DETECTORS AND SMOKE DAMPERS:
1. SMOKE DETECTORS: A duct mounted smoke detector shall be installed
in the main supply air duct, on the downstream side of the after
filters and prior to any duct takeoff, of all supply air systems
of capacities greater than 56 m3/min (2,000 CFM). Upon smoke
13
Previous Page
