HVAC is an acronym for Heating, Ventilation and Air-conditioning. It is an up and coming field which has generated a lot of interest and revenue in the recent times. HVAC systems are used to regulate the climate inside a building. The temperature, humidity and air-flow are controlled using a series of systems. HVAC is a prospective market for many investors and is in its developing stage. The HVAC industry has seen some changes in the recent time with companies encouraging people to go Green and a plethora of energy efficient devices having been introduced into the market. To work properly, the heating device should work in tandem with the ventilation and air –conditioning. Let us look at various types of HVAC systems in the market:
A split system separates the hot side from the cold side. The cold side generally consists of an expansion valve and a coil. It is inserted into a furnace, the air is blown through the coil and is circulated through a series of ducts. The hot side is generally placed outside of the building. It consists of a Condensing unit-coil shaped like a cylinder. The coil is made of a fan and a weather resistant compressor.
Hybrid-heat Split Systems:
The hybrid heat split system is an improvement over the previous split systems. It has more energy efficiency over the split systems. Some parts of the hybrid heat system are common with the split system. Both contain furnaces, evaporator coils, ducts and thermostats. But hybrid heat split system also has a heat pump as compared to the air-conditioner of the split system. This helps both in heating and cooling the building through the use of electricity. It is also more cost-effective when compared to split-system.
Duct free Split Heating and Air-conditioning System:
These systems typically differ from the previous split systems in the presence of ducts. These systems do not make use of any ducts for the flow of air. These can be installed where the typical ducts cannot go. They are a complement to the previous systems. These consist of a heat pump or air-conditioner, a compact fan coil instead of a duct, refrigerant and thermostat. The compact fan coil does the work of the ducts.
Packaged Heating and Air-conditioning systems:
These are the last type of HVAC systems. These offer a viable alternative to the split systems in case of any space constraint. The packaged systems occupy less space than the split systems and are also available in many different options from one room packages to entire home systems in a single package. These consist of a heat pump, thermostat, fan coil and also an evaporator coil in a single package. Option of dehumidifiers is also available in these systems.
Chilled water and Air-conditioning systems:
In this kind of cooling system, liquid water is pumped through the building to the chilled water coils. The water needs to be cooled down and is done so by flowing through a chiller plant. Inside it, vapor compression equipment cool the water to a lower temperature and pump the cold water to air-to-water heat exchangers. The condenser water absorbs the heat from the refrigerant in the water chiller, which is then sent to a cooling tower (heat exchanger) from where it is returned to the water chiller where it is cooled down between 4° and 7°C and pumped to the air handler, repeating the cycle.
Window units and Air-conditioning systems:
These small units are installed on the windows or a custom opening in the wall. The air indoors is cooled as fan blows it through evaporator. The heat absorbed inside is then being dispersed outdoors with the second fan blowing the air through the condenser. Window air-conditioning units can only properly cool small spaces and is not intended to cool large buildings and rooms. These can be used as both cooling or heating systems.
These systems belong to one classification of the HVAC. Many such classifications can be done based on other factors like number of areas or zones the system is being used in and also the volume the system covers.