York YCAL0065, YCAL0041 2.03REFRIGERANT CIRCUIT COMPONENTS, 2.04HEAT EXCHANGERS, 2.05CONTROLS

FORM 150.64-EG1

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.Brazed-type connections for fully hermetic refrig-

erant circuits.

2.03REFRIGERANT CIRCUIT COMPONENTS

Each refrigerant circuit shall include: liquid line shutoff valve with charging port, low side pressure relief device, filter-drier, solenoid valve, sight glass with moisture indi- cator, expansion valves, and flexible, closed-cell foam insulated suction line.

2.04HEAT EXCHANGERS

A.Evaporator:

1.Evaporator shall be brazed-plate stainless steel construction, single or dual circuit heat exchangers capable of refrigerant working pressure of 450 psig (3103 kPa) and liquid side pressure of 150 psig (1034 kPa) (Option for 300 psig [2068 kPa] available.)

2.Evaporator shall be covered in 3/4" (19mm) flexible, closed cell insulation, thermal conduc tivity of 0.26k (BTU/HR-FT2-°F]/in.) maximum.

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 -20°F (29°C) ambient in off-cycle.

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, full-airfoil cross section,

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.

3.Fan Motors: High efficiency, direct drive, 6 pole, 3 phase, insulation class “F”, current protected, Totally Enclosed Air-Over (TEAO), rigid mounted, with double sealed, permanently lu- bricated, ball bearings.

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, anti-coincidence and anti-recycle timers, au- tomatic pumpdown on shutdown, condenser fans, evaporator pump, evaporator heater, unit alarm contacts, and chiller operation from 0°F to 125°F (-18°C to 52°C) ambient. Automatic reset to normal chiller operation after power failure.

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 non-volatile memory, with programmed setpoints retained in lithium bat- tery backed real time clock (RTC) memory for minimum 5 years.

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