FORM
2.Refrigerant flow through the compressor with 100% suction cooled motor.
3.Large suction side free volume and oil sump to provide liquid handling capability.
4.Compressor crankcase heaters to provide extra liquid migration protection.
5.Annular discharge check valve and reverse vent assembly to provide low pressure drop, silent shut- down and reverse rotation protection.
6.Initial Oil charge.
7.Oil Level sightglass.
8.Vibration isolator mounts for compressors.
9.
erant circuits.
2.03REFRIGERANT CIRCUIT COMPONENTS
Each refrigerant circuit shall include: liquid line shutoff valve with charging port, low side pressure relief device,
2.04HEAT EXCHANGERS
A.Evaporator:
1.Evaporator shall be
2.Evaporator shall be covered in 3/4" (19mm) flexible, closed cell insulation, thermal conduc tivity of 0.26k
3. C o o l e r s h a l l h a v e t h e r m o s t a t i cally controlled heaters to protect to
4.Brazed plate heat exchangers shall be UL listed.
5.Installing contractor must include accomoda tions in the chilled water piping to allow prop er drainage and venting of the heat exchang er. A strainer with a mesh size between 0.5 and 1.5mm (40 mesh) is recommended up stream of the heat exchanger to prevent clog ging.
B.Air Cooled Condenser:
1.Coils: Internally enhanced, seamless copper tubes, mechanically expanded into aluminum alloy fins with full height collars. Subcooling coil an integral part of condenser. Design working pressure shall be 450 PSIG (31 bar).
2.Low Noise Fans: Shall be dynamically and statically bal anced, direct drive, corrosion re sistant glass fiber reinforced composite blades
molded into a low noise,
providing | vertical air discharge and low | |
sound. Each fan | in its own compartment | |
to prevent crossflow | d u r i n g | f a n |
cycling. Guards of heavy gauge, | P V C | |
(polyvinylchloride) coated or galvanized |
| |
steel. |
|
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3.Fan Motors: High efficiency, direct drive, 6 pole, 3 phase, insulation class “F”, current protected, Totally Enclosed
2.05CONTROLS
A.General: Automatic start, stop, operating, and pro- tection sequences across the range of scheduled conditions and transients.
B.Microprocessor Enclosure: Rain and dust tight NEMA 3R/12 (IP55) powder painted steel cabinet with hinged, latched, and gasket sealed door.
C.Microprocessor Control Center:
1.Automatic control of compressor start/stop,
2.Remote water temperature reset via a Pulse Width Modulated (PWM) input signal or up to two steps of demand (load) limiting.
3.Software stored in
4.Forty character liquid crystal display, descrip- tions in English (or Spanish, French, Italian, or German), numeric data in English (or Metric) units. Sealed keypad with sections for Setpoints, Display/Print, Entry, Unit Options & clock, and On/Off Switch.
5.Programmable Setpoints (within Manufacturer limits): display language; chilled liquid tempera- ture setpoint and range, remote reset tempera- ture range, set daily schedule/holiday for start/ stop, manual override for servicing, low and high ambient cutouts, number of compressors, low
YORK INTERNATIONAL | 75 |