Why Is My HVAC Air Filter Wet? Common Causes and Solutions

Is your HVAC air filter wet when you go to change it? This may prompt you to call for HVAC repair in Louisville, KY, without any knowledge of what’s causing the moisture. As alarming as a damp filter may be, there are a few common reasons why this occurs. 

Learn why air filters may become wet over time and what you can do to keep your HVAC system working at its best.

The Dangers of a Damp Air Filter

Residential and commercial HVAC systems rely on air filters to trap debris like dust, pollen, pet dander, and more. The filter promotes the distribution of clean air to keep you healthy as well as supporting your heating and cooling system’s function. While property owners may use different filter designs, they should always stay dry while in place. 

Even a small trace of moisture may lead to mold and mildew growth. Fungi can sprout along the filter or inside your ductwork and drastically affect your indoor air quality. Mold not only makes your indoor environment musty and uncomfortable but it can present serious health risks, including:

• Fatigue
• Dizziness
• Coughing
• Shortness of breath

These symptoms are especially harmful to those with respiratory conditions like asthma. For your health and safety, invest in regular HVAC system maintenance to prevent mold growth due to damp air filters.

Top Three Causes of Wet Air Filters

Is your HVAC air filter wet and you are not sure why? The exact cause varies but this issue typically occurs during warm weather while your air conditioner runs. Your cooling system naturally creates more moisture by pulling heat and humidity out of your space and replacing it with cooler air. 

Why would your HVAC filter get wet? Below are three common issues that property owners deal with that result in damp air filters.

1. Frozen Evaporator Coil

The air conditioner’s evaporator coil houses refrigerant which traps heat. Without a functioning evaporator coil, your system can’t complete the cooling cycle. 

Coils may freeze and prevent refrigerant from traveling through the rest of the system for the following reasons:

• Dirt and grime buildup on the coil
• Low refrigerant levels
• Clogged filter or blocked air ducts

Before condensation on the coil freezes, it can moisten your air filter. 

2. Clogged Condensate Drain Line

Ask an HVAC technician, “Why is my HVAC air filter wet?” and they’ll tell you that the condensate drain line may be to blame. Air conditioning manufacturers understand that condensation naturally occurs during each cooling cycle and build systems with a special drain to dispose of the liquid. 

During normal operation, your air conditioner will produce condensation that should flow through the condensate drain line. Water will end up outside of your home rather than remaining inside the system and reaching your air filter. However, a clogged condensate drain disrupts this process. 

Dirt and algae may appear inside these lines and block the flow of water. When this happens, the condensation has nowhere to go but toward your air filter. 

3. Leaking Drain Pan

Along with the condensate drain line, modern air conditioners also feature a drain pan. This shallow, metal component connects to the evaporator coil and catches excess water droplets that the system produces. Clogged drains can cause the pan to overflow while cracks or corrosion cause it to leak.

What to Do if Your HVAC Air Filter Gets Wet

If your HVAC air filter is wet, don’t ignore it. Keeping up with HVAC filter maintenance prevents serious problems like mold growth inside your ducts and poor system performance. Take the following steps as soon as you notice the damp filter:

• Replace the filter: Restore air filter efficiency by replacing the damaged component immediately. If you don’t have a new filter to install, consider shutting off your HVAC system to prevent particles from circulating around your space. 
• Determine the source of moisture: A quick inspection of your cooling equipment should help you uncover the root of the problem. 
• Contact a professional: Once you figure out what’s causing the excess moisture, reach out to a trained HVAC repair technician. They can recommend the best course of action, such as thawing and cleaning frozen coils, clearing clogged condensate drains, or replacing damaged drain pans. 

The most important thing to do after completing repairs is to focus on HVAC maintenance. Experts can give you tips for caring for your HVAC system throughout the year as well as perform annual tune-ups to keep everything working properly.

How HVAC System Maintenance Prevents Wet Air Filters

Are you worried that you’ll find your HVAC air filter wet when you go to replace it? As long as you keep up with routine maintenance, the filter should remain dry and efficient. Air conditioning maintenance involves a thorough checklist of tasks that prevent the top causes of wet filters. 

Technicians look closely at evaporator coils and clean any dirt on the surface to prevent them from freezing. They also check refrigerant levels to rule out leaks. If your system begins to run low on refrigerant, experts will add more so the air conditioner can handle all of your cooling demands. 

Tune-up services include inspections and cleanings of the condensate drain line and pan as well. For peace of mind, technicians also replace your air filter, among other vital tasks. 

Set a regular filter replacement schedule so your system has a new filter in place every one to three months. You should also monitor any unusual changes in your system’s performance. Invest in a professional tune-up service once a year for a well-rounded inspection of your HVAC equipment.

Discover HVAC Solutions From A1 Mechanical Heating & Cooling

Why is my HVAC air filter wet? How often should you change commercial HVAC filters for optimal efficiency? A1 Mechanical Heating & Cooling has the answers to these questions and more. 

Reach out to our experts whenever your heating or cooling system needs repairs, maintenance, or replacement. Call (502) 708-2247 for top-notch HVAC services in Louisville.