Strange Sounds from My HVAC Unit

I don’t know if comes with growing up in the country but, my hearing is pretty good.

It might come from being able to determine a certain sound from the cacophony of bugs, birds and frogs.

I can remember closing my eyes and really tuning my hearing in to a certain sound to locate and recognize it. Whatever it is, it sure has come in handy as an adult. I’m always the first one to hear something wrong with the car as we’re traveling down the road. I’m usually met with a chorus of boos but ultimately I’m right. Apparently, it is not the most endearing of qualities for some reason. Last week, I heard what I could only describe as a very faint hissing sound. It sort of came and went but I kept hearing it. Curious, I started searching through the house for the source of this hiss. I couldn’t find it inside so I went to checking the perimeter of the house. When I came to the HVAC unit, I found the source of the hissing. It was almost not audible over the rest of the noise but I knew I was hearing it. I called the HVAC pros to come take a look at the condenser unit outside because I thought it had some sort of leak. The HVAC tech said there was indeed a leak. He found a small rupture in the refrigerant line. He told me that while it was a small leak, it could have been much worse had I not caught it. The HVAC tech refilled the refrigerant and went on his way. I knew this supersonic hearing was a blessing of sorts.
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