between models as to coil configuration, air discharge nozzles, air
balancing dampers, or relative arrangement of parts. Provide automatic
valves and controls as specified in paragraph CONTROLS. Secure each unit
to the building structure. Capacity of the units shall be as indicated.
2.9.2.1
Enclosures
Fabricate enclosures from not lighter than 1.2 mm 18 gauge steel,
reinforced and braced. Front panel of enclosure shall be removable and
insulated when required acoustically and to prevent condensation.
Discharge grilles shall be [adjustable] [integrally stamped] and shall
properly distribute air throughout the conditioned space. Plastic
discharge and return grilles are not acceptable. Provide access doors for
all piping and control compartments.
2.9.2.2
Air Plenums
Fabricate plenums from galvanized steel with interior acoustically baffled
and lined with sound absorbing material that will attenuate the sound power
from the primary air supply to the room. Heat-resistant nozzles shall be
integral with or attached airtight to the plenum. Where coil induction
units are supplied with vertical runouts, a streamlined, vaned, mitered
elbow transition piece shall be provided for connection between the unit
and ductwork. Provide an adjustable air-balancing damper in each unit.
2.9.2.3
Coils
Fabricate coils from not less than 10 mm 3/8 inch outside diameter seamless
copper tubing, with copper or aluminum fins, mechanically bonded or
soldered to the tubes. Furnish coil connections with not less than 13 mm
1/2 inch outside diameter flare or sweat connectors, accessory piping
package with terminal connections suitable for connection to the type of
control valve supplied, and manual air vent. Coils shall be tested
hydrostatically at 2000 kPa 300 psi or under water at 1700 kPa 250 psi air
pressure and shall be suitable for 1400 kPa 200 psi working pressure.
2.9.2.4
Screens
Provide easily accessible lint screens or throwaway filters for each unit.
2.9.2.5
Drain Pan
Size and locate drain and drip pans to collect condensed water dripping
from any item within the unit enclosure. Drain pans shall be constructed
of not lighter than 0.9 mm 21 gauge steel, galvanized after fabrication,
and thermally insulated to prevent condensation. Insulation shall have a
flame spread rating not over 25 without evidence of continued progressive
combustion, a smoke developed rating no higher than 50, and be of a
waterproof type or coated with a waterproofing material. In lieu of the
above, drain pans may be constructed of die-formed 0.8 mm 22 gauge steel,
formed from a single sheet and galvanized after fabrication and insulated
and coated as for the 0.9 mm 21 gauge steel material or of die-formed 0.9
mm 21 gauge type 304 stainless steel insulated as specified above. Pitch
drain pans to drain. Provide drain connection when a condensate drain
system is indicated. Connection shall be minimum 19 mm 3/4 inch NPT or 15
mm 5/8 inch OD.
SECTION 15895
Page 45
Previous Page
