My Dad called me last Sunday, because she thought a rodent was inside of the ductwork. I told my Dad that it was unlikely, even though she insisted that I come over after work to check it out, when I arrived, I started looking at the heat pump plus the ductwork. I used a very bright flashlight to see inside of the ductwork. I saw no evidence of rats or mice. I didn’t even see any evidence of bugs love cockroaches, termites, or ants; My Dad told me about a loud sound that she kept hearing at evening. When she started to describe the sound, I didn’t believe it seemed love a ductwork problem at all. I believed it sounded love an issue with a heat pump, unfortunately, heat pumps plus electricity are not my area of comprehension. I could have helped my Dad with a pest control problem, but I didn’t suppose the first thing about the heat pump. I knew it was best to leave the work to a professional plus certified expert. I found a local heating supplier that offers free estimates plus I gave them a call for my mom. Waited until the repair repair arrived so I could find out what they thought about the problem. They agreed that the sounds were likely coming from the heat pump plus not the ductwork. They performed a full plan repair tune up that included cleaning all of the electrical plus mechanical parts of the system, and hopefully the plan will run better now that it has been ran tests on plus cleaned.