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4 Common HVAC Indoor Air Quality Issues

4 Common HVAC Indoor Air Quality Issues


With Americans spending 90% of their time indoors, HVAC and indoor air quality is a central concern for both building owners and occupants. This leads to a lot of people spending time indoors and suffering the negative impacts of indoor air quality (IAQ).

To prevent these problems, it helps to know what the most common air quality issues are and how to prevent them. 

From periodic duct cleaning to HEPA filters and air cleaners, there are many ways that business owners and occupants are enhancing their HVAC systems to deal with common IAQ issues. 

Let’s look at four common HVAC issues, how they affect IAQ, and how some of these problems can be fixed. 

HVAC Issues and the Problems They Can Cause

1. Irregular HVAC Maintenance - Allergen Build-up 

Many people suffer from seasonal allergies. However, these symptoms can be worsened because of a poorly maintained HVAC. Allergens like pollen, pet dander and dust mites can collect in air ducts that have not been cleaned and filters that are not replaced regularly.

Taking steps to reduce the concentration of allergens can make the space safer and more comfortable for occupants. 

How can you control allergens indoors and improve air quality?

There are many things that you can do to get fresh air in, while keeping allergens out:

  • Get duct cleaning to clear them of allergen build-up.
  • Replace HVAC filters regularly.
  • Install high efficiency particulate air (HEPA) filters or MERV 13 filters. 
  • Keep windows and doors closed whenever possible.
  • Use air purifiers throughout the building.


2. Single-Speed HVAC - High Humidity Levels 

A one-speed heating and cooling system can impact your building’s humidity. According to a study conducted in 2020, single-speed systems underperform at maintaining ideal indoor humidity. 

While high indoor humidity may not seem to be a problem, it can increase the presence of indoor air pollutants. Conversely, low indoor humidity can create a perfect environment for pathogens like the influenza viruses and even the novel coronavirus. 

How can you control humidity in your building?

If you have a persistent humidity problem, you should consider installing an underfloor air distribution system. With a underfloor air distribution (UFAD) air conditioning system you can:

  • Control humidity better than with a conventional system.
  • Maintain a more consistent temperature in the premises.
  • Reduce energy costs for air conditioning by up to 30%.


3. Moisture in the HVAC - Mold Growth

HVAC and indoor air quality

Mold growth is a pressing health concern that must be solved quickly, before it affects your
HVAC and indoor air quality. Though mold can appear anywhere, high levels of humidity and a warm environment encourage mold build-up.

It may not be completely obvious that you have a mold infestation. Some warning signs are:

  • Signs of mold growth (greasy or fuzzy; green, yellow or brown color).
  • Strong mildew smell throughout your building.
  • Frequent complaints of itchy eyes, nasal irritation, headaches and nausea.
  • Occupants experiencing allergic reactions and respiratory problems.

How can you prevent mold growth in your building?

Mold is a persistent enemy. Getting rid of it once doesn’t mean it’s gone forever. Here are a few things you can do to prevent mold from affecting your indoor air quality and HVAC:

  • Keep air ducts dry 
  • Regularly inspect HVAC drain pans
  • Replace air filters periodically
  • Apply mold inhibitors in the HVAC system
  • Reduce humidity levels in the building
  • Install a UFAD system for more evenly distributed cooling 


4. Insufficient Airflow - Pollutant Build-up

Poor airflow can be caused due to improper duct planning. Air will stagnate in an area if it does not have sufficient vents and registers. A lack of ventilation can cause pollutants to build-up and lower your HVAC and indoor air quality. 

Since most pollutants are usually odorless, you may not even realize they are affecting your health. Inadequate air circulation has the potential to cause anything from minor to life threatening ailments. In some cases, deadly amounts of radon or carbon monoxide can build up quickly in poorly ventilated buildings.

How can you improve ventilation?

There are several ways you can prevent the build-up of pollutants and improve IAQ. A few options are:

  • Installing exhaust fans in bathrooms, kitchens, and other high-moisture areas.
  • Installing a UFAD system in the building for more evenly distributed airflow.
  • Adding air purifiers in areas with poor circulation.


Switch to Underfloor Air Distribution for Better IAQ While Reducing HVAC Costs 

Traditional HVAC systems lack the temperature control and filtration required to maintain indoor air quality. If you are looking for an HVAC that improves IAQ, consider an underfloor air distribution (UFAD) system.

UFAD has been widely installed around the world for over 20 years by Airfixture. It works by pushing fresh air into the building at the floor level, while cycling out old air at the ceiling. This helps reduce the buildup of pollutants, improving IAQ.

What are the benefits of a UFAD system?

  • Improve IAQ with better floor to ceiling airflow
  • Reduced energy use and cost
  • Increased control over thermal environment:
  • Reduced repair costs due to increased accessibility
  • More environmentally-friendly than traditional HVACs. 

If you are worried about potential IAQ and HVAC problems affecting you and your employees, consider installing a UFAD system. You will ultimately save money on HVAC repairs, and energy costs while ensuring your space is filled with clean air.

Contact AirFixture today and find out how a custom UFAD system can greatly improve your building’s indoor air quality while keeping your staff safe.

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