3 Potential HVAC System Ventilation Problems For Commercial Buildings

An HVAC system, especially in a large commercial building, can require a lot of ventilation in order for the system to work. If the HVAC equipment is located in a basement or on a main floor, the ventilation needs to extend all the way to the roof in order to properly ventilate. Unfortunately, this means it is more likely that the HVAC system will run into a ventilation problem. Here is what you need to know about 3 of those potential problems.


One common concern with commercial HVAC ventilation is leaks. This can happen if the ventilation shaft is not properly sealed at some point on its way up the roof of the building. While it's a minor issue to have a single leak, multiple leaks can cause a big problem.

Try to identify leaks by placing your hand near seams that have been welded together. If you feel airflow coming out of any part of a ventilation shaft, mark the problem area and continue along the shaft. Single areas may only require additional welding to close them up.

Damaged Shaft

While a damaged ventilation shaft is quite unusual, it can happen to your HVAC system. This is when there is a section of the shaft has become disconnected from the main shaft, essentially creating a huge leak that needs to be fixed. HVAC technicians can find these sections of the shaft that have become disconnected, even if they are located behind walls, by using a camera. It could require making holes in walls in the building in order to reconnect pieces of the ventilation shaft together.

Flooded Shaft

You may have a ventilation shaft that has become flooded with rain water. Repairing it involves doing two things, which starts by having all of the water pumped out of the ventilation shaft. An HVAC technician will then need to figure out how water is getting into the ventilation shaft and seal up the leak. It could be something as simple as a cap on the top of the ventilation shaft that is cracked and allowing water to come in.

Your commercial HVAC system is definitely something that needs to be maintained over the years if you want to keep it in good condition, and the ventilation shaft is one of those parts that requires some care. If you have questions, reach out to a local HVAC technician who can provide assistance and make sure everything is working properly.