To put in simpler terms it can be said that the general definition of an HVAC is that it is a system that provides different kinds of heating and cooling services both to residential and commercial buildings along with different kinds of vehicles as per industry standards. The best thing about an HVAC system is that it offers a comfortable temperature indoors throughout the year if the system is maintained well.
When someone decides to install an HVAC system in an indoor space it is important that they are aware of certain terms closely associated with an HVAC system. They are the following:
Btu: British thermal unit (Btu) is the unit that is used to measure energy required for the heating and cooling of an equipment. It is basically the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.
EER and SEER: EER is the Energy Efficiency Ratio. It is basically a measure of how a cooling system works when the outside temperature is at a specified level. If you are buying a machine with a higher EER it means that it is more efficient and will use less energy to produce the same amount of cooling. There is a specific method to calculate the EER of a machine which your technical expertise will be able to explain you.
SEER is the Seasonal Energy Efficiency. It is the measure of energy over a single cooling season against a particular outside temperature. Generally, the residential units are rated with SEER because practically speaking SEER is a better rating as the outside temperature is not always 95 degree Fahrenheit. Just as in the case of EER a higher SEER means that a machine is more energy efficient. It must be kept in mind that SEER is variable as it changes depending on the geographical location.