Heating, venting, and air conditioning systems (more commonly known as HVAC) are prevalent everywhere in homes across the United States. They control temperature, humidity, and air quality in an enclosed space. Small critters are liable to enter through openings or by damaging the exterior to enter on their own. Mice, rats, squirrels, chipmunks, cats, opossums, and raccoons can all chew wires and leave droppings inside their temporary homes.

Recognizing animals in your HVAC unit is the first step in solving the issue. Foul odors emanate from droppings, nests, or even a dead animal. Also, if you hear noises that could be a critter scurrying around the unit. Holes or spotty patchwork on a unit can allow entry for small animals. In order to prevent entry by these creatures check your home for easy access points. If there are holes in the foundation make sure to seal them. If the ducts have issues be sure to repair them. Lastly, check your dryer exhaust vent for any animals.

If a raccoon or rat tears apart the ductwork the HVAC unit is then compromised. The hot and cool air is liable to escape to any part of a crawlspace or attic. Opossums are excellent climbers and are adept at crawling into insulation. Pest droppings that permeate the air can cause allergies and asthma for those breathing in the toxic air. In addition, the HVAC unit will not operate at full efficiency if parts of it are not functioning. This costs the homeowner efficiency and then money in repairs. In summation, the answer is a definitive yes as to whether animals can enter your HVAC system. The damage caused will not be extensive but can be corrosive if left unattended.