Air duct maintenance in HVAC systems

HVAC systems are the bedrock of managing indoor environmental quality (IEQ) and it is very critical to ensure each part of the HVAC is maintained properly. Changing air filters every 2-3 months is the most effective way to ensure clean air, however, maintenance of other components is equally important. .

One of the critical components is the air duct through which the air is circulated across the building. Other important components include the heat exchangers, evaporator coils, collector pans, fan motors, blower fan blades and fan housings. All these heating and cooling equipment affect the indoor air quality and need to be paid equal heed.

According to studies, 25 to 40 per cent of energy in HVAC systems is wasted due to leaks around doors and windows, inefficient equipment, mediocre insulation and unsealed ducts. Inefficiency in equipment is build out of untimely cleaning and maintenance of the critical components mentioned above. Moreover, along with cleaning air ducts, the blower fans should also be cleaned as this leads to reduction in air borne particles and improves energy efficiency. Similarly, evaporator coils should be cleaned along with the ducts to prevent the build-up of moisture and humidity. The collector pan below the evaporator coil which collects the water should also be cleaned so that build up of molds and bacteria can be kept in check.

The most important aspect of the maintenance of air ducts and other components is to know the frequency at which the HVAC systems need to be cleaned. Each component has different frequencies, for example the evaporator coils and collector pans should be cleaned at least once a year, the blower fans should be cleaned at least every 2 years, otherwise they won’t have a life of more than 5 years and the air ducts should also be cleaned every 2-3 years depending upon the needs.

Also, if it is noticed that there is substantial mold growth, insect and rodent infestation has increased and more than normal deposits of dust is there, air ducts should be cleaned immediately along with the collector pans and evaporator coils. Also, re-sealing of the air ducts should also be evaluated.

One of the most common pitfalls where many buildings fail to maintain the HVAC systems properly is the urge to avoid the hassles involved in the maintenance and the confusion around different frequencies for different components. To ensure that all of the above things are taken care of properly, IEQ management should be outsourced to companies who bring in a data driven and professional approach to the management of HVAC systems and make the entire process a hassle free experience.

Udayan Banerjee
Co-founder & Head of Operations, Clairco