You will find the indoor component of your cooling system housed inside your air handler. If water drips out, check for frost on the evaporator coil. If there is frost on the AC coil, then most likely, your system has frozen over. You will need to let it thaw it out again before it can cool your house. Here are the basics of how to do that:
Step 1: Switch the AC Off but Turn the Fan Blower On
Set the thermostat from “cool” to “off.” This stops chilled refrigerant from going to the outdoor compressor and prevents compressor damage, which is very expensive to repair. In most cases, it is more economical to replace on entire system than it is to repair a blown compressor.
Then, switch the fan from “auto” to “on.” By turning the system fan on, you blow heated air over the frozen coils, causing them to defrost faster. Just be sure that the cooling mode is set to “off” so that the air conditioning system does not try to start a cooling cycle.
Depending on how much frost accumulated, frozen coils can take under an hour or the better part of a day to thaw. Keep a close eye on the coils as they thaw, though. If the drain line is blocked, water will accumulate in the condensate pan and will spill out and possibly cause water damage as the coils thaw.
Step 2: Troubleshoot the Issue
Next, why did your coils freeze? Bad airflow is a common culprit, but let’s get to the bottom of what is interfering with your airflow:
- Check the filter.If your filter is dirty, airflow through it will be poor. Replace the filter monthly, or whenever you see visible dust accumulation.
- Open any closed supply vents. If any of your supply vents are closed, airflow through the system will be reduced. Vents should remain open all the time, and closed vents limits the amount of system airflow passing over the evaporator coil.
- Check your ductwork. If there are significant obstructions in your ductwork, airflow will be reduced.
- Check for obstructed return vents.If something gets caught in your system’s intake vents, that will reduce airflow throughout the whole system and will risk a freeze.
- Check your blower.An unreliable fan motor or an unbalanced fan can prevent airflow from moving over the evaporator coil as designed.
Step 3: What to Do If Airflow Is Not The Problem
Although slightly less common, air conditioners may freeze even if your system has optimal airflow. In these cases, you likely are having a refrigerant issue. Here are some common refrigerant problems:
- Low refrigerant: Perhaps your system has insufficient refrigerant. Depending on your system’s age, you may have Freon® or Puron®, which require environmental mitigations. You will need the services of a skilled HVAC specialist to fix a low refrigerant issue.
- Refrigerant Leak: AC systems are supposed to run refrigerant on a closed loop. If your system has insufficient refrigerant, then you have a refrigerant leak somewhere. You will need a certified technician to find and fix the leak and recharge your air conditioner to the proper system design level.
- Dirty Evaporator Coil: If there is dirt on the coil, air cannot reach it. You will need to have the coil professionally cleaned to prevent future freezes.
If these somewhat common problems do not feel like the trouble, then some other problem is causing your AC freeze. In this case, simply thawing the system will not solve your issue, and the evaporator coil will likely freeze again. You will need to diagnose, address, and fix the underlying problem. Give us a call today to have our best AC technicians identify and fix issues with your air conditioner.