I recently moved into a two-year-old house. In each of the three bathrooms, I can hear water dripping onto the vent. It seems to come and go, but, as long as the heat is on, it definitely drips. Any ideas what this is and what can fix it?
Luke, Huntersville, NC
There are two likely possibilities for the dripping sound that you may want to explore. The first involves condensation that could be caused by poor or no insulation around the vent pipe. The second possibility involves noise from the pipes themselves. You can contact our ARS/Rescue Rooter branch in Indian Trail, NC at (704) 545-8868 to help determine whether a plumbing or HVAC technician would be most able to assist you.
Condensation is the most likely culprit if the dripping sound is definitely tied to when the heat is running. If the vent pipe is not properly insulated, moisture could be forming on the inside of the pipe, especially if a gas water heater vent system is connected to the vent system for the furnace. If enough condensate forms, it will drip down and hit the section of vent pipe below it. If the vent pipe is extending through the attic, and it is not a double-wall pipe, and/or not sufficiently insulated, it is more likely that condensation is occurring.
If the dripping sound is coming from the pipes themselves, there are several ways this could happen. Metal ductwork could be expanding and contracting as it heats up and cools down. In this case, you should consider replacing the metal with flex duct or adding insulation around your metal pipes. Plastic pipe may have isolators that make a ticking noise when you run water. Related to that, the vent dampers could be making a ticking noise.