enclosed] [explosion proof] enclosures. Condenser fans shall be
manufacturer's standard for the unit specified and may be either propeller
or centrifugal scroll type. Unit shall be provided with a factory
operating charge of refrigerant and oil or a holding charge. Unit shipped
with a holding charge shall be field charged with refrigerant and oil in
accordance with manufacturer's recommendations. Outdoor unit shall produce
a maximum ARI sound rating of [8.4] [8.6] [8.8] [_____] bels in accordance
with [ARI 270] [ARI 370]. [Interior water source piping shall be insulated
as a "cold pipe" described in Section 15080A THERMAL INSULATION FOR
MECHANICAL SYSTEMS.] [Water-cooled unit shall be fitted with a strainer
protected solenoid shut-off valve. The valve shall be a fully automatic,
self-contained temperature regulating valve with integral thermometer.]
2.5.1
Air-to-Refrigerant Coils
**************************************************************************
NOTE: Delete the copper or aluminum tubes and the
0.076 mm (3 mil) coating except in corrosive
environments.
**************************************************************************
Air-to-refrigerant coils shall have [nonferrous] [copper or aluminum] tubes
of 10 mm 3/8 inch minimum diameter with copper or aluminum fins that are
mechanically bonded or soldered to the tubes. Coils shall be protected
with a minimum 0.076 mm 3 mil thick [phenolic] [or] [vinyl] coating.
Casing shall be galvanized steel or aluminum. Contact of dissimilar metals
shall be avoided. Coils shall be tested in accordance with ASHRAE 15 at
the factory and be suitable for the working pressure of the installed
system. Each coil shall be dehydrated and sealed after testing and prior
to evaluation and charging. Each unit shall be provided with a factory
operating charge of refrigerant and oil or a holding charge. Unit shipped
with a holding charge shall be field charged. Separate expansion devices
shall be provided for each compressor circuit.
2.5.2
Water-to-Refrigerant Coils
**************************************************************************
NOTE: In areas where poor water conditions exist or
where water conditions are unknown, the 0.001 factor
will be specified. In areas where water is known to
be noncorrosive the 0.0005 fouling factor will be
specified. Water-cooled condensers may be used for
refrigerant storage in lieu of a separate liquid
receiver, if the condenser storage capacity is 20
percent in excess of the fully charged system.
**************************************************************************
Coils shall be of the tube-in-tube, shell-and-coil, shell-and-tube, or
concentric tube type and be provided as an integral part of the packaged
unit. Water-wetted metals shall be [copper] [or] [90/10] [or] [70/30]
[copper-nickel], except that heads may be ferrous metal in systems with
chemically treated recirculating water. Coils shall be rated for not less
than 2758 kPa 400 psi refrigerant side and 862 kPa 125 psi water side
pressure service at operating temperatures. Coils shall be supplied with
water as indicated. Water supply, return and control system wetted parts
shall be copper, bronze or stainless steel. Water supply, return
connections and piping internal to unit shall be copper with brazed or
threaded copper or bronze fittings, terminating in a threaded connection.
Piping arrangement shall include valved access for recirculation of acidic
SECTION 15700A
Page 18
Previous Page
