What is a Condenser?

In the context of cooling system, when speaking for a condenser, what is on your mind?

The following article will discuss on a part that plays an important role in cooling system, a condenser. Its main duty is to cool down refrigerant. It is commonly known as a tool that absorbs the cool vapour sent from the compressor.

Condenser is included in cooling systems such as a air conditioning in cars and buildings, and freezers. It helps ventilate the heat of the vapour refrigerant at high temperature and pressure. Its purpose is to condense the heat out while maintaining the same level of pressure.

The refrigerant placed in a condenser is in form of vapour and at high temperature because it was heated and pressed at high pressure from the compressor. Once the refrigerant passes through the condenser wall, it changes from original form of vapour to liquid by aid of air and water in order to remove the heal whilst its pressure remains.

Types of Condenser

Condenser is categorised into many types according to the objective of usage. The ventilation of the heat comes in different forms which requires water and electricity to complete the cycle, hence it is important to take this fact into consideration.

Types of condensers are Air Cooled Condenser, Water Cooled Condenser, and Evaporative Condenser.

Air Cooled Condenser

Air Cooled Condenser uses air as a main hero to ventilate heat from refrigerant in order to condense the refrigerant. In general, this type of condenser is made from finned copper or iron pipes in order to enlarge the surface that is used for heat ventilation.

The air that continue to the condenser will be low, therefore, there is a need to increase the surface of the condenser. Air cooled condenser as the name suggested uses air in relate to the speed of air circulation. The design of air cooled condenser should care for the rate of air circulation at lowest motion possible but with high quality in heat transfer.

The speed of air that increased makes the fan works harder. The normal speed of air that is used to ventilate is at 2.5 and 6 metres per second, subject to change. The air cooled condenser is perfect for small refrigeration such as a refrigerator, a cooler, a cold bath which can be further categorised into the followings:

1. Natural air circulation

Finned-Tube Condenser is widely used and is made from U shaped copper pipes and thin aluminium sheet to increase the capability of the ventilating surface. Flat Tube Condenser is installed behind or underneath the refrigerators so that it can ventilate the heat accordingly.

2. Fan circulation

Heat ventilation from refrigerant uses the method of natural air circulation but making the air circulate into the condenser more, which can be divided into two types.

Chassis Mounted that is installed with the compressor and a motor where it combined all parts into one unit so called a condensing unit. This type of condenser is suitable for a small cooling system. Its set back is cleanliness as it is on the ground. Air passing through the condenser is not quite clean and may contain dirt and particles and may affect the capability to ventilate.

Remote condenser which is installed separately from a compressor. It can be used for both indoor and outdoor in which the wind direction should take into account to designate the location of the condenser. The remote condenser uses a blower to increase the amount of air passing through the surface of the condenser. Its benefits come in terms of shape and size reduction of the condenser.

Water Cooled Condenser

The reduction of heat from refrigerant by using water as the main mechanic to ventilate is to aid the refrigerant to condense. The quality of water and refrigerant that exchange making the temperature of water increases and evaporates. Water will blow vapour into the air which can be divided into two systems.

Wastewater System

Water that passes through cooling in a condenser will be transferred to waste after using. The importance of this system is to calculate the amount of water in order to specify the correct water speed.

It can be calculated by finding the balance between water and energy. The flow of water is approximately at 0.025 litre/second per 1 kW of the capability to refrigeration. It is suitable for a small condenser.

Re-Circulated Water System

Water that passes through a condenser and moving to pipes and a cooling tower to reduce the water temperature can be circulated inside and reuse. The speed of water is approximately at 0.045 and 0.06 litre/second per 1 kW.

Cooling Tower

Once cooling water drops in temperature and pass through a condenser, cooling tower will reduce the water temperature by injecting the water to lower level while the heat is being removed at the same time. The air passes through the cooling tower from the top where the air uses in the cooling tower are natural or by fan.

Fouling rates

The major variable that matter to the Water Cooled Condenser system is fouling that produced by sedimentation of minerals that come with water. Those sediments will be attached to the pipes’ walls and will reduce the capability to transfer heat and will obstruct the flow of cooling water.

In general, the producer of condensers will inform location of cleaning and will introduce scale factor which is another indicator of the coefficient of the heat transfer from the water cooled condenser.

Evaporative Condenser

 

This type of condenser is a collaboration between water and air in order to reduce the cold from refrigerant. Water is being pumped from the lower storage and sprayed into a condenser before hitting its bottom. Once the refrigerant evaporates and contains qualities of high temperature and high pressure, it attacks sprays and condenses.

Whilst the water sprays into a condenser, a fan motor sucks in air from outside to inside from the bottom of the condenser and blows them through a steamer so that they cannot escape out with the air.

By which, steam may evaporate when meeting with the heat, making the reduction in water level, and therefore, it is needed to be refilled in order to maintain the water level.

Maintenance of a Condenser and a Cooling Tower

A condenser is one of the equipment that does not need regular care, nonetheless, lubricant of a fan bearing and surface of a condenser must be double checked. The surface of a condenser should be clean at all times and should not contain dusts nor dirt because the Water Cooled Condenser may have residues.

To prevent bacteria, it is recommended to use specified residue removal and to drain out water before adding new fresh water. Then, pumps the water with the dissolvent so that it can be cleaned as a whole.

Summary

The right type of condenser is crucial in cooling system because it is a tool to help refrigerant condenses including air ventilation and heat removal from the refrigerant. Moreover, it is important to choose the right condenser that would match the tasks so that it performs at best capabilities.

For more information, please kindly contact us directly. We’re more than happy to discuss with you and give some advice in regard to cooling system and condensing units.