Air Conditioning Float Switch and Safety Switch Explained

Most people know that air conditioning units cool indoor spaces by removing heat from the air, but what many people don’t realize is that in this process air conditioners also act as a dehumidifier and remove moisture from the air. The unit functions by running the warm air inside the house across the evaporator coils, where refrigerant inside the coils absorbs heat and moisture from the air. The refrigerant then travels through a compressor that is located outside of the house. Here the refrigerant is compressed before flowing over the third component, the condenser, which condenses the refrigerant so the heat can radiate away into the air outside. So essentially the air conditioner works because the refrigerant is constantly traveling back and forth, absorbing heat from inside the home and releasing it outside, but what happens to the moisture collected by the refrigerant?

Air Conditioner Moisture

In the process of dehumidification, some moisture remains behind in the air conditioning unit before it exits the unit through a drain line. AC units also have a drain pan, where excess moisture collects if the drain line gets backed up or cannot remove excess moisture fast enough. On especially humid days, or if your air conditioning unit is not functioning properly, you might be faced with a drain pan overflow. In the event of a minor overflow you may not even notice the problem, which can lead to microbial growth or mold accumulation over time, putting you at risk for structural issues or health problems. A drain line backup could be even worse, causing a major overflow and serious water damage to your home.

What Does an AC Float Switch Do?

This is where an AC float switch comes in. Also sometimes called an AC safety switch,  AC float switches can be installed in the drain line of the air conditioner, and if water begins to accumulate in the drain line a small ball valve inside the switch will begin to float. When the ball begins float to the top of the drain line, the switch will transmit a signal to the compressor unit to turn off, preventing an overflow and alerting you to the problem before your home sustains any water damage.

AC float switches are very simple devices that can be easily installed at a low cost. Considering the high cost of repairing water damage, it’s a great idea to install a safety switch on your air conditioning unit as a simple precaution to protect your home from damage. If the safety switch is activated, the unit will turn off immediately, allowing you to clean the drain line and get your AC unit back in working condition before it causes any damage to your home. You can install an AC safety switch yourself with the right tool, or you can easily have one installed by a professional.