When Your Air Conditioner Works A Little Too Well: Common Causes Of An Iced-Over AC Unit


If your air conditioner isn't blowing cold air, the problem may actually be that your air conditioner unit has become too cold! Many people have been shocked when they open up their air conditioning units only to see a gigantic block of ice. The culprit, in this case, is that the evaporator coils are becoming much colder than they are designed to, which causes ice to form around them. The ice acts as an insulator, which exacerbates the problem since the warm air from your home can no longer heat the evaporator coils, and they're already too cold! For this reason, when your air conditioner ices over, you'll need to leave it off for a period of up to 48 hours in order to let it defrost entirely. Some common causes of an iced-over air conditioning unit are below. For many of these, you'll need to contact an HVAC professional to repair the problem:

Insufficient Airflow To The Evaporator Coils

The most common cause of an iced-over air conditioning unit is insufficient airflow. Your air conditioner works by blowing hot air taken from inside your house over the evaporator coils, which are filled with gaseous refrigerant. The refrigerant expands and rapidly lowers the temperature inside the coils. When the hot air from your house circulates around the evaporator coils, it is cooled down. When there's a problem with insufficient airflow to the evaporator unit, the temperature exchange between the warm air from your house and the cool air inside the evaporator coils does not happen fast enough. The evaporator coils will get too cold until they eventually cause the ambient moisture on the outside of the coils to turn into ice.

Lack of airflow is most often caused by a filter that has become clogged. You should change your filter every two months and always use high-quality filters to ensure that your air conditioner runs correctly. In addition to causing the evaporator coils to ice over, clogged filters can also cause the motor that runs the blower to work harder than it was designed to, which shortens its lifespan. Another possible cause it a defective blower. Listen carefully when you start your air conditioner and ensure that the fan is running. If the blower is defective, you'll need to call an experienced HVAC contractor to replace it.

Dusty Evaporator Coils

If you have been using low-quality filters that do not do an adequate job of trapping dust in the air, or if your air filter is not correctly seated inside the unit, your evaporator coils may be dusty. If this layer of dust is thick enough, it can act as an insulator that prevents proper temperature exchange from occurring inside the unit. This causes effects similar to what happens when there is a lack of airflow to the unit, as the evaporator coils will get too cold and begin to form ice crystals.

You can clean your evaporator coils with a soft brush and water. Don't use soap or detergent, as this can corrode the evaporator coils and cause them to leak refrigerant. You should also use a very gentle touch when cleaning them, as they are rather fragile and very expensive to repair if you accidentally break a coil.

Refrigerant Leak In The Air Conditioning System

Although it's counterintuitive, having too little refrigerant in your air conditioning system can cause the evaporator coils to become too cold. Your air conditioning unit is designed to operate with a specific level of refrigerant circulating through it. When levels get too low, the pressure in the evaporator coils becomes uneven. The refrigerant in some coils will expand too rapidly, which will cool the coils more than is designed. This eventually leads to the coils become too cold and forming ice crystals.

The refrigerant is not consumed by the air conditioner's operation; if your levels of refrigerant are low, it means that you have a leak somewhere in the air conditioning unit. Unfortunately, refrigerant leaks are notoriously difficult to detect, even for trained professionals; the air conditioner may only leak at certain internal pressures or outside air temperatures, or the refrigerant may be leaking in a location that cannot even be seen. You will need to contact an HVAC professional if you suspect a leak, as only they are qualified to recharge your refrigerant.

Check out a website like http://www.advancedheatingandcooling.com for more information and assistance. 


7 July 2017

Shopping For A New HVAC System

After my sister moved into my house with me, she started complaining about the temperature. I had never really thought about it before, or maybe I was just used to it, but my house was pretty cold. She told me that she didn't think the furnace was working properly, so I started checking things out on my own. Sure enough, my furnace seemed to be having some serious problems. I started looking for a replacement, and I was able to find a great furnace for much less than what I initially thought I would need to spend. I wanted to make this blog for anyone out there who might need to shop for a new HVAC system. Check out these great articles for information you might need.