What to do when your AC unit freezes up?

Living in Portland, you are accustomed to things freezing during the winter. However, it might sound strange to think that during the hottest days of the year, something could freeze up. As ironic as it might seem, during the summertime, air conditioners can freeze over. It is a common occurrence.

Most homeowners are oblivious to this possibility. This post will explain why your air conditioner might freeze up and also provide some recommendations on how to prevent the problem from happening.
Are You at Risk of a Freezing Problem?
You can evaluate your risk for a freezing air conditioning unit by checking your supply registers. Are they warm to the touch? If they are, there is a good chance that you are dealing with frozen evaporator coils. When you open the panel, check for ice. Remember, just because you don’t see ice doesn’t mean that you’re not having an issue with freezing. However, if you do see ice buildup on the evaporator coils, you know for sure that your air conditioning unit is frozen.
Who Is Joule-Thomson, and What Does He Have to Do With Your Frozen Air Conditioner?
Before we can examine why your air conditioning units freeze, you first need to understand how your air conditioning unit works. Temperature measures the amount of energy a molecule has. When the air feels hot, it is because the molecules in the air are full of energy, so they are moving around quickly.

The same thing happens in reverse. Cold air is made up of molecules that have low energy, so they move slower. This is where the Joule-Thomson effect comes into play. In thermodynamics, this effect describes how when the air and air conditioning unit is not compressed, its temperature will continue to fall as it expands and molecules slow down. But when air is compressed, the molecules become full of energy and heat up.

An air conditioner works by expanding the refrigerant that travels through the evaporator coil. This causes the air inside your air conditioning to cool down before leaving the air conditioner. The cool air impacts the air in your home, removing the hot air from inside the house.

However, when your air conditioner malfunctions, the evaporator coil may cool down an excessive amount of refrigerant, causing it to fall below the freezing level and ice over. This will effectively force your AC unit to shut down.

There are a few primary causes of AC freeze-ups. When you understand these causes, you can prevent them. There are also some simple fixes that you can do if you have a minor AC problem. If your AC freeze represents a more extensive issue, contact our technicians at Rival Heating & Cooling. We can help you get your AC working as it should again.
Fixing Issues With Blocked Airflow
If you have a freezing coil problem, your air conditioner will not run efficiently, and you will spend more money on your energy bill. One thing to check for is that your AC unit has a constant airflow. If there is no constant flow of air, the humidity will collect on the coils and freeze.

To guarantee that you have sufficient airflow moving through your house and throughout your air conditioning unit, make sure that the AC unit filters are not clogged or dirty. A clogged filter will restrict the airflow.

Purchasing a new air filter is relatively inexpensive. It is best to change it every 30 to 90 days, depending on the manufacturer’s specs. Regular maintenance is also key to preventing AC issues. According to the DOE, if you change your HVAC filter, you can boost the efficiency of your HVAC equipment by between 5% to 15%.

If your air conditioner is already frozen or you realize that your air filters are clogged, then your issue is likely a blocked airflow problem. Turn off your air conditioner and allow it to defrost. It can take up to three hours for it to thaw. Turn on your fan without activating your AC unit for about one hour. As the fan runs, change the air filter. Once you have changed the air filter and put everything back together, turn your AC unit on. It should be working normally again.
Refrigerant Leaks and Mechanical Problems
Your air conditioner is a complicated appliance that is full of moving parts that can become clogged, stuck, or broken. A fan might stop moving, the refrigerant line can kink, there may be leaks, and filters can become clogged. Just one of these issues can lead to a drop in pressure, which will cause the refrigerant to expand and become too cold.

Refrigerant is at the heart of your air conditioner's function. It is what keeps the temperature of the machine and, by extension, your home well-regulated. If the refrigerant level is low, it can cause things to freeze up. Regular maintenance done by our technicians at Rival Heating & Cooling may involve identifying minor issues early and repairing them before they become big problems. If your AC unit is 10 years old or older, it may be better for you to invest in a new machine as opposed to constantly trying to fix the smaller issues that pop up.

It is not recommended that you try to refill low refrigerant levels in your AC unit. Refrigerants are safe to use when they are housed in your AC unit or your refrigerator. However, they are best handled by professionals who understand how to keep them contained. If you think that your AC unit has a serious mechanical failure or a refrigerant leak, talk to our HVAC professionals. We may be able to help you prevent catastrophic issues from happening.
Cold Weather Outside
Your air conditioner is built to work within a set temperature threshold. During some parts of the year in Portland, nighttime temperatures can be colder than the optimum threshold. This can mess up your air conditioning unit.

You can fix this by installing a programmable thermostat. This way, your AC unit will automatically shut down when outside temperatures are below 60 degrees. If you don’t have a programmable thermostat, monitor the temperature. If you know that the temperatures at night are going to drop below 60 degrees, make sure that you turn off your AC and open your windows to let some of the cool summer air in.
Helping Residents Feel Perfectly Comfortable
At Rival Heating & Cooling, we are heating, cooling, and energy audit specialists serving Vancouver and Portland. We know that a freezing AC unit is common in our area. Many of the problems that cause frozen ACs are preventable, and our technicians are happy to perform regular maintenance to keep your AC unit working its best. Whether you need air conditioning installation, repair, or maintenance, we can help. Our team also offers ductless heat pump and air quality improvement services, as well as repairs, maintenance, and installation of other HVAC products. We have the tools, technicians, experience, and certification to get the job done right.

Save money and improve comfort with an efficiently performing AC unit. Contact Rival Heating & Cooling today to learn more.