NYC Metro Area’s HVACR Blog

Commercial HVAC, Preventive Maintenance Agreements

Your HVAC System Could be the Cause of that Musty Smell


Musty smells from your HVAC drive away customers

That musty smell is driving away customers

Few complaints drive customers away faster than unpleasant odors from mold and mildew, restrooms, or food. Lingering odors in your restaurant, health club or retail store could spell disaster for your business.

Psychologists studying the effects of odors have documented that people quickly become conditioned to odors. This means that while you and your employees stop noticing an odor very quickly, your customers notice as soon as they walk in the door, and they will be walking out the door in a hurry.

Is the odor coming from your HVAC system?

Odor problems can be surprisingly difficult to solve, and the causes are not always immediately apparent. If you’ve noticed an unpleasant musty smell, you’ve probably already tried the obvious remedies like cleaning and deodorizers.

If these haven’t helped, then the culprit may be your HVAC system. Two problems can contribute to the spread of nasty odors in your space:

  • Poorly maintained HVAC equipment that harbors moisture and generates that musty smell.
  • Poorly designed HVAC airflow can push air in the wrong direction, spreading nasty odors to areas where your customers are (like from the restroom to your dining room).

Proper inspection and maintenance can get rid of musty odors in your space

If you have an odor problem, it’s time to bring in an expert to take a look at the condition of your HVAC system. Sometimes, inadequate maintenance of exhaust systems, clogged vents or air filters, clogged drain lines can lead to water leaks and a build up of grime and moisture that causes a musty odor.

Regular maintenance of your HVAC system takes care of these issues so those odors no longer plague your space and drive away your customers.

Every day that you wait, hoping that scented candles and deodorizers will do the trick, you will be losing business. Your customers will be posting negative reviews on Yelp complaining about how the nasty smell in your restaurant made them lose their appetites.

To learn more about HVAC preventative maintenance and getting a contract that meets your specific needs, download our guide to HVAC Preventative Maintenance Contracts: How to Choose The Best One for Your Infrastructure.

New Call-to-action

Controlling odors is all about regulating air flow

HVAC systems move air through buildings. Exhaust fans, clothes dryers, built-in vacuum systems, dust collection systems, and range hoods all remove air from a space. Some ventilation systems, air conditioners and heating systems supply air, or push air into the space. When there is more air removed from an area than air supplied, negative pressure causes air to be drawn in from outside the room, resulting in negative air flow.

Conversely, when more air is pushed into your space than removed by exhaust, positive air flow is created. Generally a positive air flow is ideal for comfort, however there are some circumstances where a negative airflow is not only beneficial, but necessary.

Why is all this important to your business? Because that movement of air also moves odors with it. And, a properly designed HVAC air flow can take advantage of air pressure conditions to move odors in the desired direction; that is, away from your customers.

HVAC professionals can do that by ensuring that the amount of air exhausted out of the problem (smelly) zone is greater than the replacement air (also called makeup air). It’s a great trick to help get rid of musty smells and other bad odors that may be impacting your business.

Here are a couple of examples of how HVAC design eliminates odors:

  • Commercial kitchen ventilation systems should be designed to create a negative air pressure in the kitchen, where those strong odors are lurking, so that conditioned air is pulled from the dining room toward the kitchen. This scenario prevents odor from traveling from the kitchen toward the dining room where customers are enjoying a meal.
  • Restrooms require negative air flow so that clean air flows in, and smelly air is drawn out through an exhaust fan. Without negative air flow in the bathroom, those offensive smells can drift out into unwanted areas where they will offend your customers.
  • Wastewater treatment facilities and chemical plants can have odor situations on a much larger scale, and need specially-designed odor control devices to reduce odors in the surrounding neighborhood. However, these devices may not work as designed unless the facility’s ventilation system uses negative air flow to prevent odors from escaping before they are captured by the odor control devices.

Start with an inspection and evaluation of all your heating, cooling, and ventilation equipment by certified professionals. The inspection may reveal that design changes are needed in order to create air flow conditions in specific areas to move air in the right direction. In this case, you’ll need a contractor with the skills and experience to implement an effective solution.

More reasons to control HVAC air flow

In addition to controlling odors, there are many other situations where you want to prevent air from flowing from one area to another in your building. The use of negative air pressure can prevent not only the spread of nasty odors, but also airborne illnesses and other contaminants.

  • Kitchens also need to be designed for worker health and safety as well as odor control. Negative air flow in the kitchen reduces hazards from smoke and fire, and it also removes air pollutants generated by cooking appliances that can cause breathing difficulties for your employees.
  • Hospitals keep people with communicable diseases in negative pressure isolation rooms. Negative pressure causes air to flow into the room and prevents air, and airborne viruses and bacteria from exiting the room into other parts of the hospital. Air is drawn out of the room only through filtration systems that capture the contaminants.
  • Laboratories and manufacturing facilities working with hazardous materials need to create work areas with negative air flow, to ensure that people throughout the building are not exposed to chemical fumes and harmful airborne contaminants.
  • Health clubs with musty, moldy locker rooms will not only lose customers, but can even make them sick. Proper air flow in a health club moves air from the fitness areas toward the dry section of the locker room, and then toward the wet shower area, where it is finally expelled from the building by a powerful exhaust system. This design not only prevents odors, but also controls dangerous mold growth.