Condenser cleanliness vs Energy efficiency
In this article you will find out the effect condenser cleanliness has on energy efficiency
Take a look at our maintenance page for more information about our service plans.
The condenser is the component within the refrigeration system through which the heat is rejected. In a conventional split system AC unit the heat is rejected to ambient air via an air-cooled condenser. In larger systems the heat may be rejected to water via a water cooled condenser, then subsequently rejected to ambient air via a cooling tower or radiant cooler.
The condensing temperature
The condensing temperature is the temperature of the refrigerant within the condenser at which it rejects the heat, the subsequent loss of heat causing the refrigerant to change state from gas to liquid.
Refrigeration plant for air conditioning systems is designed typically for a condensing temperature 15-20°C above summer design ambient, i.e. 45-50°C.
The effect of condensing temperature of plant efficiency
The rate at which heat is rejected at the condenser (and therefore absorbed at the indoor unit evaporator) has a proportional impact on the power input to the refrigeration plant, and hence energy efficiency.
The greater the difference between the condensing temperature and the ambient temperature, the higher the rate of heat transfer from the refrigerant to the surronding air. Therefore a lower condensing temperature equates to a more efficient system. For every 1°C reduction in condensing temperature there is approximately a 3% reduction in the plant energy consumption.
Considerations at plant design stage
Selection of the most economical condenser, careful positioning of it, choosing between air-cooled and water-cooled version – these are factors to be discussed with the installation contractor.
Considerations during plant maintenance
Improvement of heat transfer by regular cleaning of the condenser coil, keeping the condenser position clear of debris which may inhibit airflow, maintaining the correct refrigerant levels, ensuring most efficient operation of the condenser fan – these all affect the efficiency of heat transfer, and should form part of any ongoing maintenance plan.