HVAC, which can be expanded as “Heating, Ventilation, and Air Conditioning” system, has become an essential part of every home and office.  The HVAC system is important for every building because this is the equipment that is going to provide heating and/or cooling effects for your building. These are also being used to circulate the fresh air to the interiors of the buildings thus being able to cut the bad odors and airborne contaminants indoors.

We could say that the heating and cooling system professionals are the right people to decide the right HVAC system for your home or office. We say this because there are several types of HVAC to choose from and choosing the right one only can provide you with the desired levels of comfort when at the same time enhancing your long-term savings. Now, let’s the different types of HVAC systems here…


Different Types of HVAC Systems:

Below are the different types of HVAC systems:

Split Systems:

These are the systems with combined configurations coming with an indoor handling unit, as well as an outdoor condensing unit. In this, the indoor system is found to be containing a fan along with an air-to-refrigerant cooling coil. On the other hand, the outdoor unit is composed of a compressor and a condenser coil. Why I have placed this type of HVAC at the first spot is that these are the traditional types where you have the components of the entire system both outside and inside the building. In addition to the components that are mentioned above, there can be ducts to carry the air through your home or office and a control panel or what we call it as the thermostat to control the system. Furthermore, there can be other optional inclusions like the following:

§  Air cleaners

§  Purifiers

§  Humidifiers

§  UV lamps

Staged Systems:

The staged systems can be further divided into single or multi-stage systems. Of these, the single-stage systems are popular in cold winter climatic conditions and in during hot, humid climates. This is because these systems are designed in such a way to provide the highest level of comfort during the coldest and the hottest days of the year. However, this would also mean that most parts of the year these would be operated at their maximum capacity when they are actually not required. This is where the multi-staged units come into play. The multi-staged system would save you money and energy.

Zoned Systems:

These are among the most complex configurations available today. Typically, these systems are designed to cool and/or heat individual rooms or sectors of the building by using a set of controlled zone valves or dampers inside the complex central ductwork. This way, this system would enable the users to restrict or block the flow of air as needed for the purpose of creating a heating or cooling effect in the room or sector of your choice. Thus, these types of HVAC systems are particularly useful for the larger rooms and the commercial facilities as they would enable the users to change the atmosphere as per their preferences. Several of these systems are programmable with temperature and humidity settings that can be changed. These systems would also save you more on energy and money by only heating/cooling certain regions of your house or building when you want.

Window Systems:

These types of HVAC systems are designed to cool one room/region at a time. Thus, these are found to be the most affordable of all. They operate only in a small area and they will be usually installed in a window or section of the wall. Due to their concentration, these are more often selected for single room applications and are more suitable for the users who would use only one room in a house. More often, these are found to be designed for cooling purposes. However, there are a few systems, which would give you the heating option as well. There will be a damper installation in some of these systems, which would provide the users with the fresh outdoor atmosphere by the help of a fan.

Hybrid Heat Split Systems:

Our team of experts at TopRemodelers.com says that this is an advanced version of the traditional split system (described above). When compared to the traditional systems, these hybrid ones are found to be offering enhanced energy efficiency by including a heat pump. The pump would work by either cooling/heating the refrigerant and thereby, making electricity-powered air conditioning and heating feasible. As a result of this, your building (home or office) can be heated and cooled without consuming larger amounts of electricity. Just like your traditional split systems, your hybrid heat split system is also composed of duct, furnace, as well as an evaporator coil.

Ductless Split Systems:

These systems will be the good option for the places and buildings where the conventional systems with ducts cannot fit in. I would say this type of system will be a nice complement to the existing systems with ducts. The primary reason why I say this is that these are more versatile than others. As such, the ductless systems would include heat pumps, air conditioners, fan coils, and refrigerant tubing and wires. These tubing and wires would connect your outdoor unit to the fan coil. More often, these types of systems are used as an additional unit to the conventional or hybrid systems as they these can heat or cool the regions within a building that can’t be reached otherwise.

Packaged Systems:

This is the best solution to those buildings that do not have adequate space for all the individual components of the split systems. As different from your conventional split systems that contain two units, the packaged systems would contain only one unit. This unit would contain your air conditioner or heat pump that is combined with an evaporator or fan coil. The compactness that this unit offers is the most appealing feature that attracts the people who want to heat or cool only a smaller space in a home or office.

Now, you should have understood the different types of HVAC systems. Don’t you want to know the components of an HVAC system? Yes, I have used in several places the terms like a coil, fan, evaporator, and so on. But, what are they? Getting to know all of the components of the HVAC system would help you select the right options for your own building. Without any delay, let’s move on to the learning here…



This, which is typically large, is often installed in the basement (or attic) of the building. This will be filled with hot water/air/steam and would push cold/hot air outward into the ducts.


These, which are usually installed during the construction of the building, will run through the ceiling. This is the component, which is used to transport the warm/cool air to the different parts of your home. The ducts are usually made of lightweight aluminum, although steel, plastic, polyurethane, fiberglass, and fabric can also be used in the preparation.


These are the rectangular outlets that transport the heated/cooled air from your ducts to the individual rooms or sectors of the building. More usually, these will be placed on or near to the ceiling.


This is the most visible component in any HVAC system and will be installed in a prominent, accessible wall. The thermostat might have already been programmed or it might have to set manually by the users. The main function of the thermostat is to trigger the heat exchanger or evaporator coil to start circulating the heated or cooled air whenever the ambient temperature becomes too hot or too cold.

Heat Exchanger:

This will be found inside the housing of the furnace unit. The heat exchanger will be switched on whenever the furnace is activated by the thermostat to generate warm temperature. It works by pulling in the cold air, heating it, and circulating the warmer air thus produced through your ducts outside through the vents.

Evaporator Coil:

This is found to be placed on the exterior of your furnace in a metal closure. The evaporator coil would play an opposite role to your heat exchanger. It would act by cooling the air whenever the thermostat is set to low temperatures. The cooled air will then be circulated through your ductwork.

Condensing Unit:

This will be connected to your evaporator coil and will be installed outside of the building with refrigerant gas. Whenever the refrigerant is cooled to a liquid by the heat exchange with the outdoor air, this will pump the liquid to the evaporator coil so as to get the liquid evaporated once again into a gas.

Refrigerant Lines:

These are the narrow tubes that would carry the substance to your condensing unit (as a gas) and return it to the evaporator coil (as a liquid). More usually, these will be made of copper or aluminum.

So, now we know about the different components of HVAC. Now, we shall move on to the HVAC controls.

HVAC Control System:

Aren’t you wondering how could you regulate the working of your HVAC system? Well and then, you must learn about the HVAC control system. The control system will contain a sensing device that is used to compare the actual state with the desired state and thus, would determine what action to be taken.

Direct Digital Control:

The terminal unit in HVAC, which would contain the heating coil, cooling coil, and automatic damper, is often programmable. The features of the program would include the following entities:

§  Time schedules

§  Set points

§  Controllers

§  Logic

§  Timers

§  Trend logs

§  Alarms

Building Automation System:

More complicated HVAC systems could be interfaced to something called “Building Automation System” to enable the homeowners to have more regulation over the heating/cooling units. With the help of this system, you could monitor the system and thereby, respond to the alarms. You can even schedule or change the configuration as per your needs.

Nowadays, there are more dedicated gateways like Building Management Systems (BMS) for centralized monitoring and controlling. Such gateways would provide you with a remote controlling option of all your indoor units of the commercial HVAC system.

So, now we know all about the HVAC unit components and controls. Now, let’s see how to maintain your HVAC in a healthy shape.

HVAC System Maintenance:

I would say scheduling for regular HVAC preventive maintenance service is the best way to extend the life of your HVAC system. This would also make sure that your system is working without any trouble and could attain its peak performance whenever you need it. Remember, pre-season maintenance is also very important to maintain your HVAC system in a healthy shape. For the systems that can heat and cool, perform the maintenance service during spring and fall; for the cooling system only maintenance, schedule the maintenance service at least once in a year (before the start of cooling season); and for furnace only maintenance service, perform at least once in a year (before the start of heating season).