Can drain flies get in through vents?

Question: We have always had water get into our ventilation. It's really bad when it rains heavily and the heat has to be on. It makes this gurgling noise and produces an awful sulfur smell. During the winter, some type of animal has gotten in the vents and died. We had to cover certain vents because of the smell.

Then, this summer came the drain flies. We checked all the drains and found nothing. They were coming up through the vents and now through our furnace. We are sure of their origin and what they are. The entire building sits on a limestone slab. We can't clean out the drains. What can we do?

Answer: This is a complex problem that would be impossible to completely address in this format. Therefore, I suggest you begin by calling us today and requesting a home inspection. Your Orkin Pest Specialist can identify where and how the animal gained access to your vent system. Once the moisture problems are resolved, the drain fly problem should also be under control. However, as long as there is damp soil or a possible leak from plumbing lines, drain flies will continue to be a problem.