Air Cooled Chillers – PSC

To ensure the highest level of quality and reliability in our Chillers, all manufacturing and testing procedures are carried out according to ISO 9001:2015 Quality Management system and ISO 14001:2015 Environmental Management system.

• Suction lines are insulated with closed cell foam insulation, then wrapped with a special protective material and then 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 galvanised steel cover plate, covering the entire U-bend coil side

• A coil guard is placed on the lower part of the unit, all around the perimeter, to provide protection for the unit components
• It is fabricated from gauge 18 (1.25mm) galvanised steel sheet metal and painted with Petra powder paint
• The coil guard is fitted in place by spring loaded quick turn latch, and is supported by stainless steel hinges

• Petra manufactured Cu/Cu condenser coils are available as an optional upgrade to the standard PSC chiller specification
• Coils are manufactured from seamless copper tubes mechanically expanded into copper fins
• Cu/Cu coils have approxiately twice the conductivity of Cu/Al coils and are therefore more efficient.  However, they are also more expensive and suitable for installation in corrosion-free environments
• All coils are pressure tested by dry air up to 3,100kPa under water
• Coils undergo dry cleanse after manufacturing for maximum system cleanliness

• Petra manufactured Microchannel condenser coils are available as an optional upgrade to the standard PSC chiller specification
• All coils are pressure tested by dry air up to 3,100kPa under water
• Coils undergo dry cleanse after manufacturing for maximum system cleanliness

Polyurethane pre-coating (for aluminium fins)

• A water based organic type pre-coated fin designed to give better retained performances compared to typical organic type
• The topcoat is made of hydrophilic resin of polyvinyl alchohol mix with hydrophilic lubricants
• It provides a better level of retained as well as improvement in the area of surface friction to help lengthen the life span of a punch dies
• Paint is certified as  per ASTM 117 A&B up to 3,000 hours salt fog test

Polyurethane post-coating (for aluminium and copper fins)

• Aliphatic Acrylic Polyurethane type, with high gloss finish with exceptional weathering performance characteristics
• Used extensively in virtually all industrial markets, 134 VOC provides a smooth, durable finish that has superior resistance to corrosion, abrasion and chemical exposure
• Paint is certified as per ASTM 117 A&B up to 3,000 hours salt fog test

Low Ambient Control down to 0°C

• Units can operate down to 0°C by using a combination of  on/off sequencing of the condenser fans and fan speed control
• The fan speed is controlled through pressure transmitter of each refrigerant circuit via the unit controller with a speed regulation device

Low Ambient Control down to -17°C

• In addition to the on/off sequencing of the condenser fans and speed control, a flooded condenser control design is used to enable the unit to operate at -17°C
• Multiple on/off solenoid valves on each condenser with a suitable liquid receiver shall be added to control the amount of liquid flooding the condenser and maintain condenser head pressure within the permissible operating range
• The liquid receivers used are designed and manufactured in accordance with Section VIII of  the ASME code and are marked with U or UM Code symbol stamps
• Liquid receivers of 75mm through 150mm diameter are UL listed

• These devices are used to permit the unit to operate in low ambient temperatures
• Head pressure control can be applied by varying the speed for condenser fan motors

Cooler tape heater protection down to 0°C

• Electrical resistance heating tape is wrapped around the evaporator shell to protect evaporator fluid contents from freezing at temperature down to 0°C ambient temperature
• Continuous power supply to the chiller shall be provided to maintain operation of the heater for 24 hours, 7 days a week
• This device will not protect external water pipe work connected to the unit for which additional frost protection measures are required

Cooler insulation material thickness

• The cooler can be insulated with closed cell foam insulation of 25mm, 38mm or 50mm
• The insulation density is 48kg/m³ with a k value of 0.035W/m.°K

Cooler cladding

• Cooler cladding can be aluminium, stainless steel or painted galvanised steel (made from 22 gauge (0.7mm)
• Cladding is applied over the cooler insulation

• The water flow switch is supplied as a loose item for field installation
• CE approved safety interlock to prevent operation operation of the chiller without evaporator water flow
• The water flow switch functions as a safety that assumes water flow rate with the shell and tube (Barrel) cooler and sends a signal to shut off the chiller if no water flow exists due to pump failure or other causes
• It is a paddle type flow switch
• The paddle consists of three segents that can be removed or trimmed and sized to fit the water pipe size
• The paddle is made of copper alloy

• Pressure relief valves are installed in accordance with the requirments of the ASME (Boiler and Pressure Vessel Code Section VIII, Division 1)
• The pressure is relieved by allowing the pressurised fluid to flow from an auxilliary passage out of the system to the atmosphere
• The relief valve is designed to open at a pre-determined set pressure to protect pressure vessels and other equipment from being subjected to pressures that exceed their design limits

• Heat Pump Chillers that may be used to provide heating in the winter are also available.  Please contact us for more information
• Simultaneous heating and cooling chillers are also available to provide heating and cooling to different areas at the same time.  Please click here for more information, or get in touch here if this is of interest to you

• The 120V single phase power supply is provided through the transformer that may be connected before or after the non-fused main disconnect switch
• GFI socket is used to operate electrical devices on site, such as laptops, tablets and mobile phones

Control Transformer

• The control transformer is to supply power input to auxillary compnents at 120 or 220 volts, such as (but not limited to) bulk head lights or the GFI Outlet