Central Air Conditioning Units: 7 Easy Maintenance Tips
To be honest, I have a love-hate relationship with our central air conditioning unit. That is to say, I love the central air conditioner when it's hot outside and fills the house with refreshing, cool air, but hate it when it's hot outside and quits working.
Simple Ways to Keep Your Central Air Conditioner Running Efficiently
As a homeowner for more than twenty years I have had a few repairs done on the central air conditioner that we rely on so heavily during the summer months. This much I know without a doubt, it's far cheaper to maintain this appliance on a regular basis than it is to repair or replace it.
In fact, Carrier, a leading manufacturer of air conditioners, states:
Proper air conditioning maintenance can help your unit last decades. On the flip-side, a neglected air conditioner loses roughly 5% of its efficiency each year that it operates without upkeep.
Fortunately, there are some very simple things that any homeowner can do to keep their A/C unit running efficiently and perhaps even less often throughout the warm months.
1. Keeps Plants Cut Back Around Unit
Let's face it, outdoor air conditioning condensers are ugly and it seems that homeowners will do their best to hide them from sight. Plants, fences and trellises tend to be popular ways to go about doing this cover-up.
Yet, air conditioners need an adequate amount of air flow around all sides in order to perform at peak efficiency. This is why experts recommend that landscaping and other objects be placed about three feet away from the unit itself.
Cleaning up leaves and other debris on a regular basis, as well as trimming or cutting back bushes, trees and other plants all help increase the air that your unit needs to draw into its system.
A/C Units Need Room for AirflowClick thumbnail to view full-size
2. Wash Pollen and Other Debris Off Condenser Unit
If your outdoor air condenser unit is in an unnoticeable location, it's very easy to forget about cleaning it regularly. But you don't want to neglect this very easy chore. The condenser pulls in air, and when it does, pollen and other debris often cling to its exterior. This will restrict airflow and cause a decrease in cooling efficiency and perhaps even cause the unit to overheat.
Pull out your garden hose and with a hard stream of water, working top to bottom, hose off each side of the condenser.
3. Do Not Close Any Registers Completely
With a two-story house the upper level is often warmer than the lower level even with the central air running. This is the case with our home, and knowing that hot air rises and cool air falls I figured I could easily balance the air temperature by adjusting the register (air vent) openings.
It is true that closing some registers on the cooler lower level forces more air out of the registers upstairs. The cooler air then works its way downstairs and the air temperature becomes more even throughout the house. However, by doing this the air conditioning unit may completely shut off!
In fact, when I totally closed some lower level registers, the coils in the unit froze and the A/C quit functioning. Luckily, by shutting off the entire cooling system and giving the coils time to thaw, the A/C was up and running again within a few hours.
Do not completely close registers. To balance the air temperature, registers can be slightly closed, but do not close them completely. (It took me two times to learn this lesson.) Additionally, make sure supply vents are not blocked.
Closed Registers Can Freeze A/C CoilsClick thumbnail to view full-size
4. Change the Filter Regularly
Maintaining a central air conditioning unit is all about maintaining airflow. That is why it is important to regularly change the air filter on the system.
Filter packages usually state a recommended schedule for replacement (i.e. every 90 days or so) but it really depends more on how much the unit is running and how dirty the air is.
During hot months, it may be beneficial to change the air filter more frequently. The process is often as simple as sliding the old filter out and sliding in the new one.
According to Trane air conditioner manufacturers,
...regular cleaning/changing of your filter will ensure the best filtration, increase the life of your machine, and give you peace of mind that you’re breathing easier.
5. Set Temperatures in a Programmable Thermostat
It stands to reason that the less the air conditioner is actually in use, the less wear and tear it endures. For anyone with a programmable thermostat, setting the temperature by day and time is a good way to reduce the unit's overall usage.
For example, we set our temperature higher during the daytime and colder during the hours when we sleep. It's far more efficient to program in desired temperatures than it is to shut the unit off completely and then turn it on after a day of work.
6. Keep the Sun Out
Another excellent way to keep the air conditioner from needing to run as often is to block the sun during the hottest part of the day. During the hours when the sun shines in the most, blinds or drapes should be closed.
This way, the home's interior temperature will not rise as much. Additionally, consider planting trees or installing awnings to diffuse some of the sunlight.
7. Get a Professional Inspection and Cleaning Done Annually
Before each cooling season it is a great idea to get a regular maintenance check and cleaning done on the unit by an HVAC professional. Service professionals usually inspect the control box; coils; fan motor and blades; and compressor and tubing; among other things. Additionally, refrigerant levels are inspected and adjusted if necessary, and the unit cleaned.
As the old saying goes, an ounce of prevention is worth a pound of cure. If you've ever had your central air conditioner quit working on the hottest day of the year, you fully understand that preventative A/C maintenance is definitely preferable to repairing or replacing it due to neglect.