Mold near/in handlers is a common occurrence. As a home inspector, it is one of the first places I check even.
Furthermore, mold near air handlers or inside air handlers does not discriminate towards the age of the unit. I have been in old homes where there was a serious concern coming from the air handler and the same with a brand new house!
The good thing with this type mold concern though, is it typically a simple fix. However, it can be difficult to pinpoint without a trained/experienced eye.
Related articles: A/C unit lifespan. What is HVAC?
How does mold in air handlers happen?
Mold needs two things to live:
Air handlers have two things inside of them, can you guess what they are?
Air handlers are a source of dust as it sucks in all the air inside your home. Furthermore, air handlers cool your home down, which also removes humidity from the air. The humidity is collected, condensed, and removed from the home using the condensation line.
Therefore, in order to control mold’s life inside our air handlers, we need to control dust and the water.
Tips to Controlling Dust
Controlling dust at your air handler is fairly simple. First and foremost, it is so important to have the right sized filter that is of good quality.
We wrote an article about home maintenance where we talk about the filter size and quality. But in this article, just make sure it is the right size and the filter if a HEPA filter.
Tip 2 – Clean, clean, clean.
Once you have the right, quality filter installed you should clean your air handler with a 50/50 solution of vinegar and water. The vinegar will kill bacteria and microbial growth. I do not recommend using bleach as the bleach is just too harmful to humans. Vinegar will do the trick.
Use a rag to wipe all portions of the air handler from the outside and the inside if you can. You can clean the inside by exposing the return plenum, this is typically the stand or underneath the air handler.
Furthermore, you can clean the unit by using a vacuum to suck in dust from the plenum and around the air handler.
Tips to Controlling Moisture
The second and harder part to control of the air handler is the moisture. The air handler condensates water from the coils, which are inside the unit. The coils have tracks that carefully drip the water into the bottom of the air handler to the condensation line.
The condensation line is usually made out of PVC and is in front of the unit coming out. Here is an up close picture:
So in order to control the moisture of an air handler, we need to ensure water is properly draining out of the condensation line.
The condensation line should have these attachments to help control moisture:
A float switch – this switch turns the air handler off if the condensation line gets backed up. We mention in the home maintenance article that you should pour vinegar down the condensation line to clean it every 1-3 months.
Insulation – the condensation line should be insulated. If the water inside is 40 degrees and your garage is 95 degrees, you can imagine the outside of the PVC pipe will condensate water and drip.
Clog Free & Dripping Outside – Ensure your condensation line is clog free by attaching a wet/dry vac to the outside end of your condensation line. The end of your condensation line is usually dripping next to your A/C unit and is 3/4inches wide.
An important note, you should be certain the condensation is NOT dripping underneath your unit and puddling! Ensure water is only flowing outside your home!
Other Tips to Controlling Mold In and Near Your Air Handler / A/C
There are a few other things you can do to prevent mold growth.
- Install a Ultraviolet Lighting System. Ultraviolet light kills microbial growth.
- Ensure the Air Handler is Not Excessively Sweating. If your handler is sweating excessively, it may need more internal insulation. This can happen if your air handler is in the garage. The sweat is just condensation and can contribute to mold growth.
- You may need to replace the unit. If the A/C system is older than 10 years, it might be time to replace it anyway. Read this article on HVAC life expectancy.
If you have further questions or a mold issue with your HVAC system comment below!