Why You Shouldn’t Ignore a Wet Air Filter: What a Damp Filter Means for Your Sacramento Home

wet air filterWe’re very hands-on people; it’s one of the requirements for working in the trades, and especially in HVAC. We’ve noticed that a lot of our clients are, too–just because you have the right people service your system doesn’t mean you don’t know a bit about it yourself! Last month, one of our more hands-on clients said he was taking a look at his air filter to see if he needed us to change it, and noticed it was pretty damp. He wanted to know if that was cause for concern.

We had our guys at his house later that day. Wet air filters may seem innocuous, but they’re signs of a bigger problem that can wreak havoc on your HVAC and your home if left to fester. Our client caught his in time, and if you’re hands-on like he is, we hope you will in the future as well.

Why Do I Have a Wet Air Filter?

Great question! The most likely reason for an wet air filter is that a condensate drain line is clogged, causing water to backfill the drip pan, overflow the pan, and fall onto other parts of the system–such as the filter.

The basic idea is this: Your system cools air, and when it does it produces water as a result. There’s a “bucket” to catch that water, and a drain in the bottom of that bucket to take the water away. But sometimes that drain gets clogged, and the “bucket” can only hold so much water…and eventually it overflows. When that happens, water can get all over the place, including the air filter.

Other less common causes for a wet air filter would be low air-flow (think dirty filter) or low refrigerant (possibly a refrigerant leak), both of which could cause the unit to leak water!

Because it happens when you cool air, it’s less likely to occur during our short Sacramento winters than during the summer. The only reason it happened to our client was because he’d left the house on business for a few days and accidentally set the thermostat to “cool.” But in a few months a lot of us may be turning on the ACs in earnest!

What’s So Bad About a Little Water?

Well, first off, the air filter itself should always be dry. It cleans air best that way! And that’s the job of an air filter–to provide clean air to the home. A wet air filter can spread moisture throughout the ventilation and HVAC system into the rest of the home–and if the filter remains wet for very long, it’ll be a breeding ground for mold and mildew that will also spread quickly. Before you know it, you’ll be looking at a duct and system cleaning or worse!

The second problem with a wet air filter is that the water isn’t just dripping on the filter–it’s going everywhere in the system! As you can imagine, water is bad for electrical and mechanical components alike. Rust, electrical shorts, mechanical seizing, and other issues can all result from water being inside the system.

Finally, the water won’t stay inside the system for long. We’ve had many, many calls from people with “damp carpet around the air conditioner” — a sure sign that the condensate line is clogged and the system is slowly flooding the house! Carpet, flooring, and furniture damage can all result from this; furthermore, if your unit is on a second story, you could be looking at more issues in the rooms below.

What Do I Do?

Prevention is easier than cure, so it’s important to make sure your AC is being serviced by a trusted contractor. They’ll make sure your condensate drain line is clear and won’t clog and flood. If you’re experiencing moisture in the air filter, see water in the system, or notice dampness or flooding in the surrounding area, the first step is to turn the AC off until the problem is solved. Continuing to run the system, even for less than a day, can magnify the problems.

Hands-on clients may jump to replace a wet air filter, and that’s important–but remember it’s only fixing a symptom of the greater problem. That problem is one that a licensed HVAC contractor should deal with. Unclogging condensate drains isn’t like plunging a toilet. You have to know what you’re doing. And even if you do know what you’re doing, working on HVAC equipment yourself can void the manufacturer’s warranty.

If the system has been wet for a while–often due to a “slow drain” that floods, drains, and floods again–more serious damage may have occurred. It’s another reason to have the pros come in: they’ll be able to quickly assess the situation and then do what needs to be done.

Hands-on is a great way to be, but if you notice your air filter is wet, leave it to the pros. It may be a warning sign of a problem that’s already working serious mayhem on your air conditioner! So call the guys who can figure out what’s wrong and fix the problem–with no surprises!