DSP – High Capacity

Air Cooled Condensing Unit with Hermetic Scroll Compressor

DSP air cooled condensing units are designed specifically for easy maintenance and installation for medium and large-sized air conditioning systems for commercial and residential applications such as homes, stores, shops, villas, restaurants, commercial complexes, offices, laboratories, theaters, showrooms, etc.

DSP series is available in a capacity range from 25 to 590 nominal kW (85 to 2,000 nominal MBH). Petra air cooled condensing units can be used for cooling or heating (heat pump optional). Petra air cooled condensing units are rated and certified in compliance to standard AHRI 410.

• The DSP series meets or exceeds the new ASHRAE 90.1 efficiency levels at both full and part load Efficiency
• DSP unit are constructed and engineered with noise reducing performance as the first consideration. Several features help ensure optimal noise reduction such as low noise mounted fans, foam or fiberglass insulation for the outdoor unit and compressor being mounted on vibration isolator
• The DSP units feature compact footprints and are suitable for close-spacing installation to serve the areas that have space constraints
• To ensure the best performance, all the air cooled condensing units are factory-run tested, produced in an ISO 9001-2015 listed manufacturing facility & certified according to AHRI standard 410
• Installation is made quick and easy with complete factory wiring, easy lifting provisions, factory installed options and start-up. To eliminate potential start-up problems, a complete factory- test run is performed on each unit
• Suction lines are insulated with closed cell foam insulation, then wrapped with a special protective material and finally epoxy coated. This gives further protection for the insulation against weather and other factors
• Other exposed copper pipes and headers are epoxy coated after being cleaned, to maintain pipe material and brazing protected against external conditions. All coil U-Bends are protected with a painted galvanized steel cover plate. The plate covers the whole U-Bend coil side
• Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test

• Welded structural C-channel base painted with mono component catalyzed primer sprayed paint
• 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 hermetic scroll low sound superior efficiency compressor
• Petra’s flat-shaped or V- shaped air-cooled condenser coils are designed to deliver their duties with optimum performance for all design conditions. Coils are manufactured from seamless copper tubes
• All coils are air pressure tested by dry air up to 2,900 kPa (420 Psi) under water. They also undergo dry cleaning after manufacturing for optimum system cleanness
• Condenser coils are covered with protective panels, to ensure uniform air distribution across the coil face area & provide additional protection for coil from weather elements
• Condenser fans of the external rotor type with many attractive features such as space saving, compact design, optimum cooling, full speed controllability and low starting currents
• Liquid, discharge and suction pipes are all hard copper pipes. They are formed using automated CNC pipe bending machines in order to minimize pipe-brazed joints which in turn increases system reliability
• Epoxy paint for all exposed copper piping system of the refrigeration circuit
• Components of each refrigeration circuit include liquid line solenoid valve, liquid line shut off valve, high/low safety pressure switch, expansion valve and filter drier
• 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
• Starting contactors for compressors and condenser fan motors
• ON/OFF switch for each compressor
• Control circuit breaker for short circuit protection
• Short cycling protection for compressors (time delay)
• Microprocessor controller for full management of chiller operation and safety circuits
• Power supply monitor (phase failure relay) 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

• Copper tubes copper fins coil
• Coil corrosion protection including polyurethane pre-coating (for aluminum fins) and polyurethane post-coating (for aluminum & copper fins)
• Sound reduction options including low rpm condenser fan & compressor jacket
• coil guard placed on the lower part of the unit all over the perimeter to provide protection for unit components, fabricated from gauge 18 [1.25 mm (0.05 inch)] galvanized steel sheet metal & painted with Petra electrostatic powder paint, fitted in place by spring load quick turn latch and is supported upon opening by stainless steel hinges
• Hot gas bypass consists of a mechanical valve capacity regulator used to adapt compressor capacity to actual evaporator load, installed in a bypass line between the high and low pressure sides of the refrigeration system and is designed for hot gas injection into the evaporator just after the expansion valve
• Pressure gauges for monitoring of refrigeration discharge and suction pressure
• Pressure relief valve set to open at a predetermined set pressure to protect pressure vessels and other equipment from being subjected to pressures that exceed their design limits
• Main disconnect switch used to de-energize the power supply to the chiller during servicing or repairing works because of the door interlock with an external handle that is installed on the electric panel door
• Power factor correction used to improve the power factor level which improves system reliability, minimizes voltage drops and gives better power quality
• Earth leakage relay used in electrical installations with high earth impedance to prevent shock
• Control transformer to supply power input to auxiliary components at 120 or 220 volts, such as (not limited to) bulk head light and GFI outlet
• IP 54 protection, class I electric safety bulk head light
• Ampere-meter & volt-meter used to measure the power current & voltage consumption Ampere-meter is used for each phase
• 120 volt power supply connected through the transformer to provide a 120 volt single phase circuit that is used to operate the electric appliances at site such as laptops, tablets and cell phones
• Speed regulator for condenser fan motors used to permit the unit to operate in low ambient temperature
• Dual power connection, one power entry for compressors & the second for the rest of the unit
• External over load for each compressor
• External over load for each condenser fan motor
• Circuit breaker for each compressor
• Circuit breaker for each condenser fan motor
• Nema 4x electrical panels made from galvanized steel
• Nema 4x electrical panels made from stainless steel
• Electronic expansion valve