Resorces
As a homeowner, there are a few things you can do to ensure your A/C runs as efficiently as possible without having to call out an A/C Tech. Regularly replacing your air filter and washing out your condenser are big parts of helping your unit run efficiently for years.
All mechanical things eventually break, but the difference between a system that lasts 6 years and one that lasts 15+ is a little elbow grease. Periodically checking components so that they are working as they should or replacing failing parts before they fail can help prevent a failure domino effect.
Below is more information on how you can help your system work better for longer.
Filters
Replacing your air filter is a simple and important part of ensuring proper system operation. Picking the right filter is also important. there are many different kinds of filters out in the market. Which one is best?
One Inch Filter Slide
If you have a one-inch filter slide. Sticking with a Merv 8 pleated filter will probably be your best choice. Increasing the amount of filtration will restrict airflow in the system and cause your blower motor to work harder and restrict air flow, reducing system life span and efficiency. On the other hand not being restrictive enough will cause issues too, for example using a fiberglass filter will not filter enough and will allow debris to enter the evaporator coil, causing a more expensive problem over time. If you have allergies using portable air filters will be better than using a restrictive allergy filter on your furnace.
Two-Inch Filter Slide or thicker
If you have a 2-inch thick filter or thicker, you can increase the amount of filtration. Using a Merv 11 filter will be optimal for most homes. A 5-inch Merv 13 filter will be the best choice for air filtration and system efficiency, it will remove most allergens and pollutants from the air, and usually last around a year or longer depending on indoor conditions.
Below is a video of filters being tested for filtration, and air restrictiveness.
Washing out condenser
In Salina ks, we have a lot of cotton trees. In some areas, it seems like it snows year-round. Unfortunately outside condensing units will suck up all that cotton preventing the system from "breathing". Washing out the condenser is something all homeowners should do at least once per year.
If the system can't move air across the heat exchanger and reject heat outside, this will cause the system to work harder, reducing system efficiency and increasing operating temperatures. Hotter than normal temperatures can damage electrical parts, increase wear on the motor windings, break down lubricating oil, weaken or damage run capacitors, and decrease the life span of the system.
On the system below, the unit was running extremely high pressures and temperatures, Luckily the system had a pressure safety switch that turns it off when unsafe pressures are reached. Most A/C units don't have this safety device. Under these conditions, the AC is consuming lots of energy, the compressor will get extremely hot, oil is slowly breaking down and turning into sludge, contamination in the system is going up, and depending on how long the system runs like this, you'll be taking years of useful life out of the system.
Electrical components
Not recommended for unlicensed individuals to do. Electrocution can cause serious injury or death.
Looking for loose connections, measuring power draw from individual components, and ensuring all capacitors are measuring within spec are a few things to do to ensure proper system operation.
Loose connections will cause high resistance, higher resistance means more power has to go into your system to operate, this can become a fire hazard, and all components before and after the connection can become damaged.
Measuring power draw and doing a general check on operation can give you a good idea of the condition of the system. System power drawn above the data specification can be a tell-tale sign of something approaching failure. Knowing of possible issues before they happen can help you plan against sudden and unexpected pricy repairs.
Checking capacitors is an easy way of ensuring your motors run as efficiently and smoothly as possible. A capacitor acts like a battery, it takes incoming energy and sends it into one of the windings in the motor, helping the motors start and run smoothly. Usually, when a capacitor fails it will stop sending current to the one of motors' windings, causing the motors to not run and overheat trying to start. The worst that can happen if the system is not maintained is if the capacitor doesn't fail, but instead becomes weak. When a capacitor becomes weak, the system will operate like normal, but it will cause the other motor windings to work harder and draw higher power than necessary, it will increase the internal temperature of the motors and wear down the windings, break down the oil reducing the effectiveness of the lubricant, and permanently reduces system performance and life span. A 30-dollar part turns into a few hundred-dollar repair or, if the compressor windings melt and ground out, a few thousand.
filters being tested for filtration, and air restrictiveness.