HVAC System Maintenance

Spring Cleaning for Your HVAC System

Spring is finally getting started (for real this time?), and you’re probably getting the feeling that it’s time to declutter the house and get things fresh and ready for warmer temperatures.  One of the most important systems in your home, the system that can mean the difference between comfort and misery this summer, needs just as much attention as the rest of your house. Your air conditioning system has been waiting quietly all winter, so follow this spring cleaning checklist to get your A/C unit ready for the heat.

Spring Tune-Up

First, consider scheduling a spring service call by a licensed heating, ventilation and air conditioning (HVAC) contractor.  Unless you have a heat pump that’s been doing double duty warming your home in the winter, your air conditioner has been sitting “off” for many months and may need more TLC than you know how to provide.  A spring HVAC tune-up will check refrigerant levels, thermostat control, air flow and air temperature levels, plus a variety of technical functions. When an HVAC technician performs the tune-up, broken or worn-out parts can be replaced right away while it’s still nice outside, so your system doesn’t go down when it’s really hot and humid.
Even if you don’t get a spring tune-up from a contractor, there are some simple steps homeowners can do to prep their systems this spring.


replace your hvac filterReplace the filter

Did you know that a dirty air filter can cost an additional 5% – 15% on your monthly utility bill?  Even worse, a filter that hasn’t been changed in many months or years can be so dirty that air struggles to flow through it.  The A/C fan will work harder and harder to pull air through the dirty filter, eventually causing motor failure and an expensive repair or even a system replacement.

Filters are cheap, easy to install, and come in a variety of sizes and efficiencies for your HVAC system.  Do some research on a filter’s “MERV” rating and see if a higher MERV filter might improve the indoor air quality (but note that the higher the rating, the more dust it will catch– So the more often you will need to change it to avoid constricting air flow).  Also, get in the habit of changing your filter regularly, maybe even monthly, depending on how dusty your indoor environment is. Changing your air filter regularly is the single best thing a homeowner can do to maintain the operation and efficiency of their HVAC system.

Remember to remove any outdoor condensing unit covers & debris

If you put a weather cover on your outdoor condensing unit at the beginning of winter (not a common thing in North Carolina’s changeable weather), always remember remove the cover before starting the A/C.  Running the A/C with a condenser cover on even for a few minutes can cause serious damage to the equipment due to lack of air flow — It’s like the unit is suffocating for breath!

Clean away any debris from your outdoor unit such as leaves and sticks, and trim back plants.  It’s best to have three feet clear around the condensing unit if possible. If the condensate drain is near the condensing unit, clean out any trash blocking the flow of water from the pipe.  A backed-up drain line can cause thousands of dollars’ worth of interior damage if water cannot drain out of the pipe.

The condenser coil itself may be dirty and should be washed off, but do so carefully as the coil is easily damaged if not cleaned properly.  Unless there is caked on mud, cleaning the coil is as simple as spraying it with a garden hose, but try to avoid getting water on the electrical connections.  Do not use a pressure washer or metal brushes unless you have experience using them to clean coils.

Look for damage around the condensing unit

Hail, falling limbs, ice, and snow can cause damage to the outdoor unit even if it’s been covered.  Check around the unit for damaged refrigerant pipe insulation, broken drain lines, missing electrical covers, or any physical damage to the condenser coils.  If you find damage, call an HVAC contractor to help with the proper repair.

Clean the supply and return vents

If dust has accumulated on the inside supply and return air vents (called “grilles” in HVAC lingo), wipe them down with a damp cloth.  If the return grille is especially dirty and removable, take it off and wash it with dish detergent and water. Once the grilles are cleaned, go to each bathroom and see if the exhaust fan covers are dusty.  Most homeowners don’t think to look “up”, so they never see dusty and dirty exhaust fans. The fan cover may be removable and can be cleaned with soap and water in the sink or vacuumed.

Walk around to see if the supply and return vents are open or closed.  Closed vents can whistle, play havoc with the temperature balancing in the house, and add stress to your blower motor that can shorten its life. It may seem intuitive and energy-saving to close off the central air conditioning to rooms you’re not using, but a supply vent is not like a faucet. To maximize the life of your system, avoid closing vents, and do so only when you have found no other way to keep a room comfortable.

Consider a thermostat upgrade

Your thermostat is the brains of your HVAC system.  If the thermostat is older, and particularly if it is not digital or “smart”, consider a thermostat upgrade.  The money you spend upgrading your thermostat will quickly pay for itself with energy savings. Digital 7-day programmable thermostats let you set on/off schedules for each A/C unit.  For example, you can schedule the system to turn off when you leave for work and turn back on before you usually come home, saving money on your utility bill when the unit is off. If you don’t want to turn the unit totally off, programmable thermostats can raise or lower the house temperature when you are away.  You will still save money, since the unit doesn’t need to cool the house down as much.

For more control and further energy savings, consider installing a “smart” thermostat and incorporating the HVAC system into your home automation system.  Smart thermostats work with WiFi and your smartphone to see real time energy usage and can automatically modify preset schedules. Smart thermostats provide additional control, such as the ability to change the temperature from anywhere, and they can learn over time how your home responds to outdoor weather and can adjust your programmed schedules to reduce unit runtime while keeping the house comfortable. Some models even allow you to set up a vacation mode ahead of time, so you don’t need to remember at the last minute or return to an uncomfortable home.

Programming a thermostat can seem like a daunting task if you do it alone.  Your thermostat manual will have a step-by-step guide how to set the schedules.  If the manual isn’t helpful, YouTube has plenty of videos on how to correctly program a new thermostat and get the maximum performance from your system. Or call your local HVAC contractor for advice – They should be happy to help you in person or on the phone, and this service may even be free if you have a maintenance agreement with them.

Test your air conditioning system

Once you’ve completed this checklist, switch the thermostat to “cool” and turn the system on.  After a few minutes you should feel cold air blowing out of the vents. When the cold air is flowing, look at the indoor air handler to make sure there are no water or air leaks or even strange noises from the system.  The air should not smell moldy or like old socks (a common problem in heat pumps), but should be cool and crisp. When the system has run for half an hour or so with no noticeable problems, you and your HVAC system should be ready for the summer heat and humidity.

If you have any questions regarding your HVAC system or home air quality, contact Comfort Monster. Our team combines the most HVAC experience that the Triangle has to offer.