Maintaining your HVAC systems not only protects the equipment, but also protects the people in your building from discomfort and IAQ concerns, and protects you from a lawsuit.
There are many ways to make sure that indoor air is kept at appropriate levels
Clean evaporator and condenser coils (once or twice per year): Evaporator coils are a place that mold grows best. In addition to constant dampness, the supply side of the coil is in contact with outside air and the dirt that isn’t caught by filters.
The condenser coil degrades quickly because of dirt. It doesn’t have an effect on indoor air quality, so cleaning it at the same time you clean the evaporator coil will improve energy efficiency.
Inspect fan, bearings, and belts (twice annually): Even though fan, bearing, and belt operation don’t have a direct impact on IAQ, you should still inspect these pieces as part of your preventive-maintenance plan. Cleaning the blades on a small fan can take an hour or more; cleaning larger fans, especially those with multiple wheels on a single shaft, can take quite a while.
Check to see if fan motors are running in the wrong direction. This may not be obvious because fans can still supply flow if they’re running backwards. Clearing the labels on the fan housing, pulleys, motor, and wires can prevent this problem.
Inspect area around air tank (twice annually): Water can pool around air handler allowing the mold to grow there. Mold near the air intake means that spores could be sucked into the ventilation system and brought into your building. Check for standing water around the air-handler.
Clean and adjust dumpers (annually): Improper dumpers are one of the common problem in HVAC equipments, and this can negatively affect indoor air quality. Operating properly, dumpers keep the compressor from running when the outside air temperature is lower than approximately 60 degrees F. If they’re not kept clean and lubricated, they stick, denying free cooling potential or overloading the cooling coil with too much hot outside air.
The above are the various ways by which the maintenance costs of HVAC system can be reduced.