Coil 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 minimum 0.076 mm 3
mils 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 shall be
suitable for the working pressure of the installed system. Condenser may
be used for refrigerant storage in lieu of separate receiver, provided that
storage capacity is 20 percent in excess of fully charged system. Coil
shall be dehydrated and sealed after testing and prior to evaluation and
charging. 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.
2.7
CONDENSER, WATER-COOLED
Condenser shall be [remote mounted, tested and rated to ARI 450] [an
integral component of a water-cooled condensing unit, be tested and rated
to ARI 520]. Condensers shall have safety provisions conforming to ASHRAE
15. Coils shall conform to ASME BPVC SEC VIII D1 or UL 207, as applicable
for maximum and minimum pressure or temperature encountered. Condenser
heads shall be removeable and have flanged side inlet pipe connections
which permit access to or removal of the tubes. A separate condenser shall
be provided for each compressor circuit. Fans shall be propeller or
centrifugal type as specified in paragraph Fans. Fan motors shall have
[open] [dripproof] [totally enclosed] [explosion proof] enclosures.
2.7.1
Unit Casing
Casing shall be weatherproof and enclose all unit components. Structural
members and sheet metal for the unit casing shall be constructed of
galvanized steel or aluminum. Casing shall be fitted with lifting
provisions, access panels, removable legs, and fan and heat rejection coil
guards and screens.
2.7.2
Condenser Coil
**************************************************************************
NOTE: Normally 70/30 copper nickel performance is
superior to 90/10 copper nickel in brackish water
and salt water. Where conditions are not
detrimental to 90/10 copper nickel, incorporate same
as an alternative acceptable material. Use the
higher fouling factor for open systems.
**************************************************************************
Condensers shall be of the shell-and-tube type with the coolant in the
tubes. 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. Unit shall be rated for not less
than 2758 kPa 400 psig refrigerant side and 860 kPa 125 psig water side
pressure service at operating temperatures. 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 scale removal chemicals and isolation pressure taps
to determine pressure drop and water flow. Performance shall be based on
SECTION 15652A
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