Everyone knows that summer in Wisconsin is hot. Due to the humidity caused by our thousands of lakes, temperatures can feel unbearable at times. That’s why losing AC during the hottest months of the year is unpleasant and dangerous.
When we think of an AC unit, we associate it with ice or cold temperatures. However, if you notice that your coils have frozen or see condensation on any part of your unit, this is not a sign that your air conditioner works. Instead, it indicates a significant problem with the unit.
If you notice frozen coils on an AC unit, you should contact a professional immediately to solve the problem. Leaving it for too long can cause other parts of the machinery to fail, which leads to even more costly problems.
Here are the main signs that your HVAC unit has frozen evaporator coils and how to fix them.
What Are Evaporator Coils?
AC units work by pumping hot indoor air through their systems to convert it into cool air. An essential component of this process is the evaporator coils, which help regulate heat exchange in air conditioners.
Evaporator coils hold liquid refrigerant, which helps cool down warm air by absorbing its heat. This refrigerant then becomes a gas after interacting with the hot air. The unit then cycles out cool air through the blower and into your home.
Evaporator coils are essential to the cooling process. Though it seems like this exchange process should cause them to freeze, evaporator coils should not reach freezing temperatures. Instead, they should hover at around 40 degrees Fahrenheit, which is cold, but does not produce ice.
Symptoms of Frozen AC Evaporator Coils
- You have an icy outdoor refrigerant line
- Your AC won’t cool your house down
- The condensate drain pan has overflowed, or the condensate drain line has a clog
- You can see ice or condensation on the AC coils
- There is excess condensation and moisture around your unit (such as on walls, dripping off the machine, etc.)
It is essential to turn off your AC unit immediately if you notice frozen coils, moisture, or warm air coming from it. After doing so, call an AC professional to come to check out the problem.
AC experts, such as those working at our Milton HVAC servicing company, have years of experience in the industry. Thus, they can spot and solve a problem quickly and efficiently so you can continue to enjoy your AC throughout the summer.
Though these symptoms often indicate frozen coils, there are sometimes other causes. That’s why it’s best to call a professional. However, there are some minor troubleshooting methods that you can try by yourself beforehand.
What Are the Main Causes of Frozen Coils on AC?
If you have frozen coils on the AC unit, the problem may stem from various underlying issues. These problems include:
- Dirty coils
- Poor airflow
- Low outdoor temperatures
- Drainage or leakage issues
- Low refrigerant levels
- Old air filter
1. Dirty Coils
Though you may not have realized it, air conditioners become dirty. It is essential to clean them regularly by hiring an AC contractor for annual maintenance appointments.
When dust gathers on and around the evaporator coils, it adds strain to the functioning of the unit. Thus, the evaporator coils must work harder to cool the air, resulting in cooler temperatures. The coils freeze due to a lack of absorption of hot air.
2. Poor Airflow
A lack of proper airflow to an AC unit’s blower can also cause frozen coils, as there is not enough hot air to balance out the cold refrigerant. Often, dirty or improperly fitted air filters are the culprits of poor airflow.
The consensus is that you should change your air filters every 1-3 months, although this advice varies depending on the filter itself and who you ask. A dirty air filter can easily block the proper airflow and create problems.
Sometimes, objects or dust may have blocked other components of the HVAC unit, which can lead to the same problem. Faulty ductwork, dirty heat pumps, or even a burnt-out blower can lead to an airflow problem.
3. Low Outdoor Temperatures
If you run your air conditioning when it is 60 degrees Fahrenheit or less outside, the evaporator coils can freeze. This most commonly occurs when temperatures are hot during the day but drop at night. Be sure to turn off your AC in case the temperature drops.
4. Drainage or Leakage Issues
Evaporator coils also work to dehumidify the air. The drain pipe typically guides this water away from your home. However, if there is a clog or hole in the pipe, it will not function properly.
Thus, collected condensation will leak into your unit. In turn, this condensation can end up on your evaporator coils. It will either appear as condensation droplets or ice.
5. Low Refrigerant Levels
You rarely need to top up liquid refrigerant in an air conditioning system. However, the refrigerant can drip out if there is a leak, lowering the level. Because there is not enough refrigerant present in the AC system, this can cause extra strain and lead to icy coils.
What to Do Before Calling an AC Professional
Before you call in a professional AC contractor, you can try to thaw the coils or check and replace your air filter.
Though it’s implausible that thawing the coils will solve your problem, it is worth a shot to see if they refreeze. In this case, you should completely turn off your air conditioning (or set it to fan mode) for a few hours. Wait for the ice to thaw before turning it back on.
Ensure that you wipe down the system and clean up the water as the ice thaws. Then, turn your system back on to see if the coils refreeze. If they do, contact an AC professional.
You should also ensure that your air filter is clean and properly fitted to your AC unit. Sometimes, expensive air filters can cause more problems if the fabric bunches up or the thicker material clogs airflow.
First, make sure to buy the air filters recommended by your manufacturer. Second, change your air filter frequently to evade problems.
If neither of these options work and your evaporator coils continue to freeze, call in an expert. They can locate the problem and quickly solve it to get your AC working.
How to Prevent Frozen AC Coils
The best way to prevent frozen coils on AC units is to schedule annual maintenance appointments. During annual maintenance, a knowledgeable technician will come to your house to inspect your AC system. They will also clean out dust and debris and resolve minor issues.
During annual maintenance appointments, the repairman will often suggest parts that you should replace and possible future repairs. Following this advice will help you avoid more expensive problems in the future. Technicians catch them early before they get worse.
Experienced HVAC Repair Company in Milton, WI
If you need a maintenance specialist for either frozen coils on your AC or preventive maintenance, contact Rocky Valley Services. We have dedicated almost two decades to repairing heating, HVAC, and AC units, so you can rest assured that our technicians are repair experts.
Call or text us at for a service appointment today. You can also learn more about our AC repair services by checking our website and helpful blog topics.