Water Cooled Water Chiller with Screw Compressor-WPSA

-Petra’s water-cooled liquid chillers (WPS) with a wide range of capacities and exceptionally high efficiencies, were designed to meet customer requirements for a variety of applications.

-Petra WPSa chillers offer state-of-the-art low sound, high quality and reliability, optimized performance, and a compact physical footprint.

-Petra WPSa chillers with semi-hermetic screw compressors and R-134a HFC refrigerant are 100% factory tested and commissioned to ensure efficient performance at specified operating conditions.

Standard Features

-Welded structural C-channel base painted with mono component catalyzed primer sprayed paint.

-The base is equipped with welded brackets for heavy-duty lifting lugs.

-Structural members are made from gauge 15 [1.8 mm (0.07 inch)] tubular cross members that are semi-welded with stainless steel fasteners. All members & panels (side & roof) are painted with oven-baked polyester electrostatic powder paint.

-Suction gas-cooled semi-hermetic twin-screw compressor with variable slide valves allow the chillers to match actual load conditions, delivering exceptional part-load performance.

-High-efficiency direct expansion (DX) shell and tube type coolers and condensers with inner grooved tubes to optimize the cooler’s efficiency.

-Coolers and condensers are tested and stamped for a refrigerant side design pressure of 1,000 kPa (145 Psi) and a maximum water side working pressure of 1,500 kPa (220 Psi).

-Independent refrigeration circuit per compressor.

-Liquid, discharge, and suction pipes are all hard copper pipes. They are formed using automated CNC pipe bending machines to minimize pipe-brazed joints which in turn increases system reliability.

-Epoxy Paint for all exposed copper piping systems of the refrigeration circuit.

-Components of each refrigeration circuit include liquid line solenoid valve, liquid line shut off valve, liquid line moisture indicator sight glass, high safety pressure switch, and replaceable core type filter

-The unit is a fully charged unit with R-134a refrigerant.

-Electronic expansion valve: Electronically Operated Step Motor flow control valves, intended for the precise control of liquid refrigerant flow. Synchronized signals to the motor provide discrete angular movement, which translates into precise linear positioning of the valve piston. Easily interfaced with microprocessor-based controllers.

-Compressor electronic current monitor and overload protection through the controller.

-Free terminal for remote ON/OFF connection.

-Free terminal for general alarm output.

-Control voltage is 220-240V for all components.

-Single point power connection for each electrical panel.

-Circuit breaker for each compressor.

– ON/OFF switch for each compressor.

-Control circuit breaker for short circuit protection.

-Short cycling protection for compressors (time delay).

-Control transformer mounted & wired that shall supply all unit control voltage from main unit power supply to internal components such as (not limited to) solenoid valves, compressor motor protector, compressor crankcase heater, and microprocessor controller.

-Microprocessor controller for full management of chiller operation and safety circuits.

-A power supply monitor (phase failure relay) is used to protect the power circuit against over or under voltage conditions and against phase loss or loss reversing conditions.

-NEMA 3X with IP54 minimum enclosure standard electrical panel. Two separate panels, one for power & the other for control.