How to Maintain Your HVAC System


How to Maintain Your HVAC System

Maintaining HVAC Systems not only protects the equipment, but also protects your home from discomfort and protects you from costly repairs. Your HVAC system includes your heating, ventilation and air conditioning systems. Generally, HVAC refers to the entire system including air ducts, vents, and the equipment used to heat a home or building. The equipment in your HVAC system is essential in keeping your home or building comfortable, and thus, it is important to keep a regular maintenance schedule for your HVAC system.

Here is a list of maintenance tips and measures to take in order to keep your HVAC system running efficiently and reliably.

Filter Capacity

Filters, and their ability to remove microorganisms, use ASHRAE’s standard, which assigns efficiency ratings to filters called a MERV. The higher the MERV rating, the more efficient the filter is in removing microorganisms and smaller particles. In general, a MERV rating of 11 or higher is recommended for your HVAC system. Filter type can also make a difference in your indoor air quality. Pleated filters, for instance, made of cotton and synthetic fabrics may present a higher up-front cost, but the fabrics can boost efficiency and the pleats increase the filter’s effective area.

Replacing Filters

Over time, filters capture dust that can become a food source for mold. Filters are made to be replaced frequently, and you need to make sure you are doing so. Depending on the type of filter you purchase and the amount of dirt your HVAC system collects, you should be replacing your filter every one to six months. If you aren’t sure how often to change your filter, simply inspect it each month to determine its effectiveness. If after one month your filter is covered and its airflow is limited, you’ll know how often to replace your filter.

Cleaning and Treating Evaporator and Condenser Coils

Evaporator coils, which are continually damp, provide one of the best places for mold to grow in your HVAC system. Additionally, the supply side of the coil is in contact with warm, humid outdoor air and the dirt that makes it past your filter contains the nutrients required for mold to grow.

The condenser coil is exposed to unfiltered outdoor air, and suffers considerable degradation due to dirt and debris. While the condenser coil doesn’t affect your indoor air quality, cleaning this coil while cleaning the evaporator coil will improve your HVAC system’s energy efficiency. Coils that have significant microbial growth are typically difficult to clean. The bacteria create a sticky biofilm that locks particles to the growing organism. Some molds develop long branches that assist the bacteria firm like cement. You will need an effective, high-quality cleaning solution to effectively remove all microorganisms.

Fungal growth is also difficult to clean from metal surfaces. You may be tempted to use a cleaning agent that is high in acid to remove fungal growth. However, these aggressive cleaners can actually damage the metal surfaces you’re trying to clean. Keeping your coils clean through frequent maintenance and appropriate treatments will dramatically reduce the time required to complete the cleaning, and will save you money in the long run.

Mold grows quickly, and a freshly cleaned coil can become moldy again in a short amount of time. It is important that your treat your HVAC system’s coils with antimicrobial treatments that disrupt the reproductive cycle of mold spores, inhibiting the growth of mold.

Inspect Air Intake

You’ll want to take the time to know where your air intake is located. Water can pool around air handlers, especially those mounted on roofs. As with any area where water exists, mold can grow. Mold that is near the air intake will increase the likelihood that mold spores will make their way into the ventilation system. Make sure you do not have standing water around your air handler, removing any standing water around your air intake that you come across.

Cleaning and Adjusting Dampers

Improper damper operation is one of the most common issues with commercial HVAC equipment. Dampers that are not operating properly can negatively affect the quality of your indoor air, and can also lead to increases in energy consumption. When operating properly, dampers keep your HVAC compressor from running when the outdoor temperature falls below 60 degrees Fahrenheit. Unless they are kept clean and well-lubricated, your dampers will stick, preventing your HVAC system from maximizing its cooling potential when dampers are closed, or overloading the cooling coil with too much hot outdoor air when opened.

While maintaining your dampers, all moveable surfaces should be cleaned and lubricated. If you have a service technician come out to do this, it should take approximately 15 minutes if there aren’t any further issues with your damper. After cleaning and lubricating, the damper should be able to run through its full range.

Cleaning Air Ducts

The need to clean your air ducts depends heavily on how well maintained your HVAC system is. While there is no real consensus as to how often, or when, to clean your air ducts, it all depends on the dirt load that makes it into your ducts. It is recommended that you inspect the supply side and return air ducts every two years. If the inspection reveals contamination, you should have the ducts cleaned. The general rule of thumb is if you find dirt, have your air ducts cleaned. Unfortunately, cleaning your air ducts is no easy task, and you will most likely want to hire a contractor to do it correctly.

Rachael Jones is a Staff Writer for DIYMother.

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