Skip navigation

Serving the Communities of North Central Florida since 1998

Traducir sitio al español

Call us in Lake Butler & Lake City


Touchstone Heating & Air Inc. Blog

Can My Air Conditioner Rust?


Anything made of ferrous metal can potentially rust, and that includes your air conditioning system. Is this a common occurrence that you should worry about? And how would rust start to develop on an AC in the first place? We’ll get into that below, as well as help you know when you should call our team for AC repair in Lake City, FL.

Humid Weather vs. an AC

First, the bad news: corrosion on an air conditioning system is more common in a place like Florida because of the high levels of humidity. Rust and other types of corrosion are something we have to deal with more often than in drier climates. Your air conditioning system is built to avoid corrosion for many years, but the basic exposure of metal to water vapor can eventually cause it. On the upside, an air conditioner has to be extremely old before this type of rust settles in, and you’ll probably have already had your AC replaced for other reasons before this can happen.

Condensate Drainage Problems

The more immediate worry when it comes to rust and your air conditioner is the condensate drainage system for the AC. When your air conditioner is running, the indoor evaporator coil absorbs heat to cool down the air. As the cold refrigerant evaporates to draw in heat, it also causes moisture in the air to condense along the coil’s surface. This moisture drips off the coil and down into a shallow pan located underneath the coil, where a pump moves it down a drain and line until it drips outside.

If something goes wrong with this condensate drainage, it can cause several problems, such as overflowing the pan and tripping a limit switch that will shut off the air conditioner. It will also cause a rise in humidity inside the air conditioner—and then you can run into problems with corrosion. 

The main area of worry is corrosion on the evaporator coil. This will cause the coil to lose efficiency as it has a harder time absorbing heat. But the even bigger concern is that it will cause refrigerant leaks—one of the biggest concerns an AC may face. Losing refrigerant not only means a drop in heating capacity, it puts the compressor in danger of overheating and burning out. A burnt-out compressor usually means the whole AC must be replaced. 

Other parts of the AC can corrode because of this moisture increase: the drain pan, the blower fan blades, even the metal ductwork. 

What You Can Do

Rust on an AC doesn’t automatically mean it’s finished. But it does mean you need professionals to service it as soon as possible. Our technicians can often remove the rust and clean off the area. In some cases, we’ll need to replace a heavily corroded part, such as one of the coils. 

If you want to know the best way to prevent rust, the answer is an easy one: always schedule annual maintenance for your air conditioner. During maintenance, our technicians clean and tune-up the system, which will help prevent a build-up of moisture inside the AC. We recommend maintenance in spring, but if you haven’t done it yet this year, it’s not too late.

Call Touchstone Heating & Air Inc 24/7 for exceptional customer service!

Comments are closed.