Facility Design Guidelines - Facilities Management - University of ...

ecirculating systems shall have a means to pre-cool and dehumidify outside
air before being mixed with the return air rather than cooling the entire
supply airstream to dehumidify and then reheating. A chilled water coil,
heat recovery device or other method approved by Facilities Management
may be used.
o) Sequence will specify if fans run continuously or can be shut off. Supply,
return, and exhaust fans shall be interlocked as required.
p) AHUs should have manual override to run unit with high outside airflow (for
venting odors from new carpet/furniture, floods, etc.)
q) In buildings that do not have other fire/smoke detection, the AHU smoke
detectors shall be used to alarm the DDC system. The AHU supply and
return fans will run continuously but the outside air dampers shall be closed
by occupancy sensors, carbon dioxide controls, or by the EMS during
unoccupied mode. If smoke enters an AHU, the fans in that AHU shall stop;
however all other fans in the building shall continue to run if allowed by
code.
r) Where perimeter heat is needed at large windows and exterior walls, it shall
be interlocked with AHU/zone control. Perimeter heat will normally be
supplied from a closed building LTHW loop with a converter served by the
University MTHW system.
s) Freeze protection shall be provided on all air handling units. Freezestats
shall stop the supply and return fans, close the outside damper, and open
the heating coil valve. Where DDC is used, the freezestat controls shall be
completely independent of the DDC system.
t) Blender sections shall be provided on all AHUs other than single pass units
to ensure that the outside air and return air are adequately mixed.
5) Identification
a) All piping and equipment in mechanical equipment rooms and central plants
shall be completely painted according to the “Scheme for the Identification
of Piping Systems”, ANSI A13.1 and the “Safety Code Color for Marking
Physical Hazards”, ANSI Z53.1, latest revisions.
b) All piping in buildings shall be identified by means of alphabetical stencils
and color codes, showing contents of the piping and the direction of flow.
Piping shall be identified at 30’ intervals, on both sides of penetrations
through walls and floors, and at each directional change.
c) All valves shall also be identified with stamped brass tags or discs secured
with non-ferrous beaded chain. Valve numbers shall be engraved or
stamped as large as possible on tags (1 inch by 2 inches) or discs (1.25 inch
diameter) attached to the valves by 10-gauge brass "s" hooks. Provide a
framed valve schedule in mechanical rooms.
d) All motor driven equipment, HVAC components, and major electrical boxes
shall be individually numbered on the drawings by the A/E and have
corresponding number plates on the equipment. (Example: For unit
heaters, use UH-1, UH-2, etc., even though both units are of the same size
and type.) All designations shall be integrated with and distinguished from
existing designations.
BSRV 4 HEATING, VENTILATION, AND AIR CONDITIONING 179