Energy Efficiency in Air Cooled Chillers

by ccampbell


An air-cooled water chiller removes heat from water or other process fluid by use of a cooling system that then dissipates that very same heat into the air. The energy efficiency is given by the chiller COP. Now days, if you want to use chiller for temporary purpose, rather than spending whole amount on new item, you can also hire Rent A Chiller for the equipment.

The chiller operates by Local Electrical Contractor using the change of state of a refrigerant gas which when forced through an orifice at high-pressure changes state from a liquid to a gas, absorbing heat through the chiller evaporator device . This cold expanded gas then travels to the chiller refrigeration compressor where it’s compressed into hot, dense gas and pumped to the chiller condenser. the quantity that the compressor can pump, the refrigeration gas used, and therefore the operating conditions determine what proportion heat is removed. At the air-cooled chiller condenser the refrigerant is forced by the compressor through smaller copper tubes that have thin aluminum fins mechanically bonded to them. Ambient air is then forced through the condenser coil by the chiller fans. This causes the recent refrigerant gas to condense into a liquid, changing state, and releasing the warmth that the gas collected at the chiller evaporator. The waste heat is then over excited into the ambient air by the fans. The liquid is then forced through the orifice and therefore the process starts again. Whеn уоu need supplemental cooling оr уоu саnnоt install traditional air conditioners bесаuѕе оf impracticality оr cost, a commercial air conditioning Brisbane іѕ a great solution. The heart of the chiller is that the refrigeration compressor. this is often a pump that uses electricity to pump refrigerant round the system. counting on the appliance like size or operating temperature, a special compressor pumping technology is employed . Smaller chillers use refrigeration compressors like rotary compressors, scroll compressors, and reciprocating compressors. Larger chillers use refrigeration compressors like reciprocating compressors, screw compressors, absorption compressors, and centrifugal compressors. Each sort of refrigeration compressor can operate more or less efficiently within the air-cooled water chiller counting on the water or glycol outlet temperature required, the ambient air temperature conditions, and therefore the chiller refrigerant used. The efficiency of the chiller compressor is given by the COP or Coefficient of Performance which is that the ratio of kW of warmth removed to kW electrical input required. the upper the chiller COP is, the higher the energy efficiency. for instance a COP of three means for each 1 kW of electrical input, 3kW of warmth is faraway from the water. A chiller COP of 5 means for each 1kW of electricity input, 5kW of warmth energy is faraway from the water.

Typically chiller COP will vary as follows:

  1. Holding the chiller condensing temperature constant: a lower chiller evaporating temperature will use more electric power per kW heat removed and therefore the chiller COP are going to be worse, while a better chiller evaporating temperature will use less electric power per kW of warmth removed and therefore the COP are going to be higher.
  2. Holding chiller evaporating temperature constant: a better chiller condensing temperature will have a worse chiller COP that having a lower chiller condensing temperature.

A customer’s process cooling requirement will determine the operating temperature for the air-cooled water chiller. for instance an air con chiller would require water typically at 7 deg C outlet from the chiller evaporator and 12 deg C return. this is able to require a chiller refrigerant like R407C which is ok for ambient air environments of up to 45 deg C.Where a better chilled water outlet temperature is required a chiller refrigerant gas like R134a would be acceptable and this has the additional advantage of allowing the chiller to work in much higher ambient conditions – for instance – chillers within the Middle East and chillers in Australia – remote locations like mine sites – are often located where the ambient air are often 50 deg C or above.