St. Louis HVAC – Is There a Mold Problem in Your Facility?

December 31, 2015


The HVAC system in commercial buildings provide a suitable environment for mold growth.

The heating, ventilation, and air conditioning (HVAC) equipment in a commercial building is more susceptible to mold growth than other equipment. Maintenance and engineering managers can play a major role in preventing mold growth in a commercial building.

The Key Problem Areas

Molds need water, food, air, and the right temperature to grow. Unfortunately, commercial HVAC systems provide a suitable environment for mold growth. For example, the indoor environment usually provides a variety of food sources, such as cardboard, wooden structures, building furnishings, papers, and fabrics.

One way to discourage mold growth is by reducing moisture in the indoor environment. Some managers prefer using chemicals, sprays, and fungicides for mold control. Using fungicides helps to kill mold but does not provide a permanent solution to the problem. Molds residing in the HVAC system may still survive. In most cases, eliminating molds from the HVAC system requires implementing a pre-emptive plan. Maintenance managers need to develop a detailed mold prevention plan and seek professional help when required.

Lack of Guidelines

There is a lack of standard guidelines on how to prevent or control mold growth in commercial facilities. Most states, except Texas and Florida, do not have any federal mold regulations. However, some organizations and groups have published best practices for mold prevention and treatment.

Maintaining the Components of a HVAC System

The HVAC system is a major source of moisture that supports mold growth in a commercial facility. Improper installation and maintenance of the HVAC system may cause mold to grow faster. Regularly monitor the components of the system to check for any signs of mold growth.

  • Coils and drain pans – Cooling coils help to remove moisture from the air. The moisture turns into water and flows through a drain pan to a deep seal trap. If the coils and drain pans are not regularly cleaned or maintained, water may accumulate in the system and cause mold to grow.
  • Humidifier and dehumidifier equipment – It is important to keep the duct linings clean and dry to prevent mold growth.
  • Outdoor air dampers – Keep the screens and grilles of the HVAC system regularly cleaned to prevent dust particles from accumulating on the surface.
  • Air filters – Keeping the air filters clean and dry is important as well. Replace the air filters when required.
  • Ducts – Regularly monitor and maintain the ducts. Keep the components of the ducts clean and dry and repair any water leakage in the system as soon as possible.
  • Return-air plenum – Prevent entry of any material or supplies to the plenum. This helps to maintain the airflow and discourage mold growth.
  • Cooling towers – In order to keep the cooling towers clean and dry, regularly check the quality of water. A chemical treatment may occassionally be needed. Install drift eliminators to prevent sediments from accumulating on the cooling towers.

It is also important to inspect the outdoor areas where the HVAC system intakes the air. Make sure that the air is not exposed to materials such as bat droppings or bird droppings that support mold growth.

For 30 years, Scott-Lee Heating Company has been serving industrial customers in the St. Louis Metro area. We provide mechanical services, pipefitting, sheet metal fabrication, and comprehensive HVAC maintenance programs. Call us at (314) 200-0788.