It was faint at first. I’d catch a whiff of something actually off-putting, however then it would fade. I thought there may have been something stuck in the garbage disposal. I kept cutting up lemons and putting them down the disposal thinking it would do the trick. It didn’t. I was lighting scented candles and leaving windows open, to no avail. I simply couldn’t figure out where the smell was coming from. It was stronger in some rooms than others however it was spreading throughout the house. When I noticed the dog pawing at an air vent, the light cooked on over my head. I got on my hands and knees for a close sniff at the vents. That’s when I knew something had died in the air duct! Judging from the cat’s reaction to the smell, I figured it was a mouse, knowing there was a dead creature in my heating and cooling ducts was a terrifying thought. I had to get the little guy removed and whatever parts of my HVAC plan it had touched, thoroughly cleaned. Some HVAC companies told me to call creature control first to remove the mouse. I didn’t have the patience for that. I finally found an HVAC serviceman who agreed to remove the rodent. Turns out it was an unfortunate chipmunk that caused the foul smell the air handler had spread throughout my home. The HVAC serviceman removed the carcass, cleaned the area of HVAC duct where the chipmunk died and changed out the filter for the oil furnace and air conditioner. He ran a check on the entire heating and cooling plan then advocated I consider adding an UV air purifier to help with dog dander. I decided to go for it. I only want wash air inside my home from now on.