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Posted 11/14/2017

Basic things you need to know about Air Conditioners

Basic things you need to know about Air Conditioners

Air conditioning is an expensive way to cool your home but sometimes a necessity. While most homes in the United States have air conditioning especially in areas with warmer climates, some people choose to have heat pumps in cooler states. It can be a luxury to have a central air conditioning system built into the foundation of the house. Since it makes such an important part of our daily lives, it is important for consumers to be well informed about how their air conditioning systems work.

Let’s take a look at 4 basic ways to be more vigilant of your air conditioners and be able to maintain them for longer. In order to repair or replace the cooling unit, you should seek the help of a qualified HVAC expert.

How your air conditioner works

In order to cool your home the air conditioner transfers heat from the inside of your home to the outside of your home. Additionally, air conditioners supply cool air to your home by sucking out the heat from the existing air. There are a set of evaporator coils present inside the air conditioner. These are filled with a nitrogen cooling liquid commonly known as a refrigerant. As the warm air blows over the set of cold pipes known as the evaporator coils, it is cooled and then blown outwards with the help of fans. The liquid refrigerant changes from a liquid state to a gaseous form to absorb the heat from the air. The refrigerant is then pumped to the exterior of the house to a separate coil where it changes back to a liquid form to give off excess heat to the surroundings. This exterior coil is known as the condenser because of the condensing process that takes place to convert gas back to liquid form similar to moisture on a cold window glass. The compressor is a pump that is used to move the refrigerant back and forth between the two coils in order to change the pressure. This is to ensure that all condensation and evaporation takes place in the appropriate coils.

The whole process is powered by a motor attached to the compressor. The whole process ultimately puts out three times the cooling energy than the compressor input. The transformation of the refrigerant from a liquid to a gaseous state and then back make the system energy efficient and use much less energy than used by the compressor.

Understanding BTUs

BTU is an abbreviation for British Thermal Units and is a unit used to measure heating and cooling energy. A ton of cooling is defined as the output of 12,000 BTU per hour of cooling energy. A regular window air conditioning unit is usually about 1 ton whereas central air conditioning units can vary. A two ton unit is sufficient for a small home but a large home might need upwards of five tons.

Common air conditioner problems and why they happen

Air conditioners have come a long way since the time of the ice blocks. They are complex machines with many small working parts that depend on a variety of factors for them to work perfectly. Air conditioners are of a specific size meant to take the load of the house’s cooling needs. They have a limited capacity for refrigeration storage called the “charge”. Only a certain amount of air can flow across the coils. If there are any alterations in any of these factors, the system will start to malfunction usually indicated with less cooling, blowing warm air or knocking sounds emerging from inside the unit.

In case the internal room temperature of the house is too high due to having more people or appliances, the air conditioning has to work on the double just to maintain a comfortable temperature.

In case of refrigeration leaks, you will get warm air out of the unit. Constantly running the unit with no refrigerant will cause further damages as it struggles to keep up with the high loads.

If the condenser grows weak it is unable to disperse heat to the outdoors efficiently and coverall cooling capacity may be reduced especially at higher temperatures.

In drier regions such as the Southwest of the United States, similar issues occur with reference to the evaporator coils. Higher airflows were helpful and lower airflows were damaging.
In humid regions it is the inverse. Higher airflows lead to lower dehumidification, causing high humidity levels. However if the airflow gets extremely low, it can cause the evaporator coil to freeze up and adversely impact the performance. This ultimately damages the compressor unit till it finally gives up. This will rack up the electricity bill and provide zero cooling.

How filters work

All modern day air conditioning systems have filters in them, though some may be hard to reach. They can be found at the point of entry in the return grill or in special slots at the mouth of the ventilation ducts. These are flaps of translucent plastics with a mesh texture. Filters do exactly what the name suggests. They ‘filter’ or remove particles from the air to prevent them from reaching the air conditioning unit. This also rids the air of pollutants such as dust, pollen and carbon monoxide.

Over the course of time, filters get clogged with more waste that affects the efficiency of the cooling system. This also increases resistance and reduces the flow of air. Regular cleaning of filters is a good way to extend the life of the cooling system and provide optimal performance. How long it takes for the filter to get jammed depends on usage, location of the house and the size of the filter. Bigger filters take longer to get blocked but it is still good practice to conduct bi-monthly cleanings (that is once in two months).

It might seem like a good idea to remove the filter completely to avoid cleaning them but then the dust build ups will be directed towards the evaporator coils and cause eventual failure. Replacing old filters with new ones is a lot less expensive.


Video: How It Works