How To Find a Leak In Your HVAC System

About two months ago, a customer called us to tell us their air conditioner just wasn’t keeping up with the heat—and it wasn’t even really hot yet!

Low Refrigerant

I inspected their system and determined that it was low on refrigerant, so I charged it up. I also offered to put a special dye into their system that could help us spot a leak.


This dye is a bright fluorescent green, and it’s easy to see with a black light. The dye itself can also seal over small leaks in your system, or at least slow them down. I added the dye to their system and told them I’d be back in a couple of months to check on it.

What The Dye Tells Us

Before the two months were up, they called back to tell us their system was not cooling. When I checked for the dye I found some at the bottom of the evaporator coil. While this isn’t the leak itself, the dye here tells me that the compressor is not pumping at all!

The Compressor

I went outside to check over the entire unit. The capacitor looked fine, but as I suspected, the compressor was not pumping. One reason a compressor might not work is overheating, so I sprayed it with water for 10-15 minutes to cool it down. No change.

I tested several other components. Finally, I put a hard start kit in the unit. This got the unit to start up, but it did not sound good. The compressor sounded rough.

Options Once a Leak is Detected

The unit was cooling now, but it was clear it wouldn’t last long. I let the customer know his options. We could patch the leak, and his system would still limp along for a while. But with a leak and a noisy compressor, its days were likely numbered. He made the decision to go ahead and replace the unit.

Your Next Step

If you are having any problems with your system, we’d love to come take a look! We have your best interests at heart. I will do my best to fix your system, and I will give you all the options. It will always be your decision to keep fixing the unit for as long as possible or to change to a new system.

Give us a call at (972) 423-1279.