Rusted AC Drain Pan – What To Do?

A metal material, when exposed to water, will immediately rust. So, we conducted thorough research to answer the question, what should you do if the drain pan of an air conditioner is rusty? 

To solve the issue of a rusted drain pan, you can replace the pan or follow these steps to refinish it:

  • Clean the drain pan using water with dish soap and a brush to remove mold and rust buildups.
  • Thoroughly dry the pan; you can use a dryer or hot air gun for this process.
  • Get sandpaper and remove as much rust as you can.
  • Clean the drain pan once more to remove all the powdered rust.
  • Use a rust converter for the last process. Coat all the areas with damage and let them dry.

Prevention is better than cure, indeed. And it would be best to perform the above cleaning method carefully. To know more about the do's and don't for your air conditioner, read on! There is so much to learn about drain pans that might help you avoid future air conditioner issues.

Air conditioner unit outdoors in side yard of a brick home in hot summer season. No people. - Rusted AC Drain Pan - What To Do

What To Do In A Rusted Air Conditioner Drain Pan?

Water leaks typically cause a rusted drain pan. And to avoid a rusted drain pan issue, you must prevent water leaks first and address them immediately if identified. Applying a preventative coating or a pan seal to the drain pan is the answer.

You should use one to seal all the holes that cause the leaks. This preventative measure will stop the drain pan from rusting and damaging your air conditioner.

In addition, it can also help to prevent the growth of mold, mildew, and fungus that might reduce the air quality of your indoor air. The existence of mold, mildew, and fungus in your air conditioner will lead to possible respiratory conditions for you and your family. 

If you can't correctly clean and repair the rusted drain pan or prevent water from leaking, we suggest replacing the pan to avoid further air conditioner damage. You can buy it yourself if you know the measurement of the drain pan. But if you want to change it flawlessly, you can always opt to call an HVAC professional for help.

Prevent Air Conditioner Drain Pan Repair 

ventilation system installation and repair service. hvac technician at work

After cleaning the drain pan and applying a rust converter, it would be best to use a sealer. You can choose between different preparations. There are acrylic, epoxy, and polyurethane sealants. However, you must be very careful with selecting silicone-based products. Some of them don't adhere well.

You can accomplish sealing in two ways. A two-pack epoxy liquid adhesive is the answer if you want the simplest. You should follow the instructions on mixing and pouring it into the drain pan. If need be, utilize a blade or small piece of wood to spread the epoxy. Use just enough mixture to coat the pan. And see if the instructions require a second coating for better sealing. 

And the second method you can use is a polyurethane or waterproof acrylic sealant. You can use either of the two to put into the areas with damage with a caulking gun.

Why Is The Drain Pan Rusty?

Rust in a drain pan will occur if you let water sit on it for an extended period and if you don't maintain it. It would be best to check your air conditioner regularly. 

Furthermore, if you notice that your air conditioner drain pan is looking orange and corroded, it may have:

  • a leak in the condensate pipe
  • a drain pan leaking
  • a clogged line

Why Is It Important To Remove Rust From The Drain Pan?

steel brush for drill clean off old metal sheet with rust

Removing the rust from the air conditioner's drain pan improves its appearance, yet its significance extends beyond looks. If you leave the rust on your drain pan unchecked, it can lead to structural damage to your air conditioning unit components.

In addition, it can affect the performance and reliability of your air conditioner, contaminate the indoor air, and reduce the air quality.

Repairing The Drain Pan Vs. Replacing The Drain Pan

Drain pans come from galvanized steel with a narrow gauge. Because of their construction, it may be difficult to render a long-term repair once they begin to rust. So, removing the old pan and replacing it with a new one is what we highly recommend.

However, if you consider upgrading your drain pan, make sure you can get replacements first. When you remove the rusted pan, you will likely worsen any damage.

  • You must isolate the electrical power before working on the air conditioning unit.
  • And you should close the fuel line.
  • Gently remove the drain pan to replace it.

And as much as possible, be careful not to damage the other air conditioner components such as the coils, wiring, and piping. Lastly,  you must check the drain line and clean it while the drain pan is out. You have to make sure that it is secure and does not leak.

How To Fix A Clogged Drainpipe

Dirty drainpipe from air conditioning

The most common cause of drainpipe clogging is bacteria or mold buildup in the drainpipe. A clogged drainpipe causes the water leak and the rust issue on the drain pan. And it is a good thing that you can fix it even without the help of an HVAC professional.

To repair, you must:

  1. Turn off the air conditioning unit.
  2. Empty the drain pan. You can utilize a wet/dry vacuum.
  3. Remove all the debris from the drain pan.
  4. Thoroughly inspect the pan for any existing rust.
  5. Go outside to check the end of the drain pipe. See and remove anything that blocks it. Make sure that it is free from any blockages.
  6. Pull and remove the cap of the drainpipe. It would be best to clear all the blockages in the pipe using a small wire brush.
  7. If you notice that the drainpipe seems clear, you should pour a mixture of water and bleach into the drip pan. Doing so will help stop the mold and bacteria from coming back anytime soon.
  8. Put the cap back on the top of the drainpipe.
  9. Turn on the air conditioning unit.
  10. Once you finish turning it on, check if it works better. It should be operating smoothly and clear again.

How To Prevent Drainpipes From Clogging

Air compressor or air condenser unit located on support outside building to heat released transferred to surrounding environment

Preventing drainpipes from clogging is very important. Doing so will save you money from future repairs and maintain the efficiency of the entire air conditioning unit.

1. Clean the air conditioner filters regularly

Dust is one of the primary causes of clogging in air conditioner drain pipes. Regularly cleaning the air conditioner filters will stop the dust accumulating in the evaporator coils. Cleaning the air filter at least twice a month would be best to prevent blocked drain lines. Also, it will help your air conditioner work at its best performance.

2. Flush the drain lines frequently

If you flush the drain lines frequently, it will effectively help prevent blocked drain lines. And it will keep the air conditioner drain lines clean. In addition, we suggest you use a mixture of water and bleach to exterminate all the mold, mildew, and bacteria that exist in your air conditioner's drain lines. Moreover, if you don't have bleach available, you can opt to use vinegar as it could also work the same as bleach.

3. You should create or install a condensate trap

If you want to prevent the air from entering and escaping its pipes while running, installing a condensate trap would be best. The trap will also help stop pollution from penetrating the air handling unit and causing damage to your air conditioning unit.

4. Hire an HVAC professional

Hiring an HVAC professional to check your air conditioning unit is an excellent way to prevent potential drain pipes blockages. Not only that, but they can also diagnose the entire air conditioner and pinpoint what could be the possible issues that might or currently exist. You can have a professional check it at least once every year.

Wrap It All Up

If you want to avoid spending a lot of money on air conditioner repairs, it would be best to regularly check your air conditioning unit. However, if you can't check it by yourself, you can always opt to ask for an HVAC professional's help. A rusted drain pan won't do any good to your air conditioning unit, so clean it immediately or replace it if necessary.

We hope you find this article helpful. And if you want more of our help, you can check out the posts below or visit our website and find more articles you want to read.

No Water Coming Out Of AC Drain Pipe – What’s Wrong?

Should Air Be Coming Out Of My Condensate Drain Line?

How To Drain An Air Conditioner (And How Often?)

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