Your HVAC ductwork can be quite vulnerable to pests; it's difficult for you to get in there and eradicate bugs or rodents, and they can access the ducts easily through any of the vents in your house or through any small cracks and chinks. The outdoor unit can contract pest problems as well since it's a relatively sheltered spot, and it's not sealed up tight enough to keep mice out.
If you discover or develop an HVAC-related pest problem during winter, you may have to call an exterminator, especially if the pests have gotten into your ductwork. Here are three pest problems your HVAC system may contract during the colder months.
The outdoor component of your unit is especially vulnerable to pests, who may decide the unit a great place to bed down for the winter once you've quit using it in the cooler fall temperatures. Unfortunately, having pests in the unit can cause problems — both for you and for them — when the unit turns back on in the spring.
Rodents can do plenty of damage while they're nesting there, too. They'll likely spend time engaging in typically destructive types of rodent behavior such as chewing through wires and blocking things up with their nesting material.
Like mice, some types of insects look for a warm place to stay during the winter. Your house may be just the place they're looking for, and your HVAC ducts may be just the route they need to get there. Ladybugs, for example, need somewhere to basically hibernate. They won't eat your house like termites or eat your food like cockroaches, but they can still be a nuisance.
Cockroaches may also start to move indoors for the winter, but unlike ladybugs, they're not there to hibernate. Instead, they'll seek out food sources throughout your house. If you see them coming out of your air vents, you might want spray roach poison there, but try to refrain. The poison will just blow back out the next time the air turns on.
Even if you don't use your ducts for heating, you don't want to have residual poison hanging around when you start using your AC again in the spring. So you can try placing bait pellets and traps rather than spraying in and around the vents. Or if a lot of insects are inside the ducts already, you'll want to call an exterminator right away, then have the ducts cleaned by a professional HVAC service.
Mice can fit through a
dime-sized hole and rats through a quarter-sized hole. This can make it easy for them to invade your home through a vent with no screen or with a slightly damaged screen, for example. They can then make nests in the insulation surrounding your ducts. If you have any flex or plastic ducting, they can easily chew through it as well, creating air leaks.
Mice problems are common during winter because rodents who live outside during the summer are now seeking shelter. Like cockroaches, they can then use the ducts as roadways to get anywhere they want on their quest for food.
If you find yourself with a pest problem involving your ducts, you'll have to take a multi-step process to get things back to normal. First, you'll need to have the pests exterminated, and make sure you seal up any possible entrance points to your home so you don't find yourself with a reinfestation. Then you'll need to have your ducts repaired and cleaned professionally.
