Sanitizing my ductwork

A month ago, I woke up in the afternoon and the temperature control was set to 76°. I live alone, and I didn’t remember setting the temperature control to 76 degrees. I thought it was an unusual irregularity, so I assumed I was sleepwalking, but a few afternoons later, I came to the lake house from running a few errands and found the cooling system running. I had the heat pump running, when I left that afternoon. I was starting to think I might not be in my right mind, until I talked to a few of my associates. I told them about the unusual temperature control problems, and they proposed calling a Heating, Ventilation, and AC professional! They believed either a malfunctioned control board or faulty wiring could be the problem. Since my associates didn’t think I was mad, I decided to contact the dealer. I told them about the unusual temperature control issues, and they agreed with my associates’ opinion. The HVAC dealers sent a contractor who came to the lake house yesterday and reviewed my temperature control. She removed the cover and fiddled with a few odd-looking wires. She asked what I spilled on the temperature control, and I was actually confused. I didn’t pour anything on the temperature control. The Heating, Ventilation, and AC contractor showed me some dried liquid. The contractor said I needed a new temperature control, because the liquid had caused some wiring troubles. I was absolutely frustrated, until I remembered my sibling was in the neighborhood last month, called him on the cell phone, and asked if he spilled something on the temperature control, then he grew silent on and I heard him sigh. He admitted to tripping in the hallway, while carrying a can of beer.

temperature control unit