July 24, 2017 Energy Air Share this post Should you buy the biggest air conditioner you can afford? Bigger isn’t better in this case though. With HVAC systems, it’s important to pick the right size for your home, not the largest air conditioning unit you can afford. Learn why buying a bigger air conditioning unit doesn’t give you any benefit over a properly sized, smaller unit. How Should an Air Conditioner Work? Your air conditioner has two jobs: cooling the air, and dehumidifying it. Your air conditioner works by pumping refrigerant from the condenser outside through skinny plastic tubes that lead into your air handler. The refrigerant is run through a metal A-frame, your evaporator coils. Your air handler sucks air from your home inside of the air handler through the air filter and into the unit for processing. The air passed through the condenser coils, which are cold because of the refrigerant running through them. The water vapor inside of the air becomes dense as it’s chilled, and condenses into water droplets. These water droplets collect on your condenser coils, dripping off into the condensate pan when it’s full. What Happens When My Air Conditioner is Oversized? When you buy an air conditioner that is larger than your home needs, it seems like it would do the job better. In reality, oversized air conditioners don’t work as well. In a normally functioning air conditioner, the build up of water droplets on the coils causes old water to drip down into the condensate pan when new water collects on the coils. Water droplets build up on an oversized air conditioner’s coils too, but it actually dehumidifies less air because they don’t have to run as long to satisfy the cooling load. That means that there is not as much water droplet build up on the coils in an oversized system. Unless that water actually condenses and makes it to the outside, you haven’t really dehumidified your air. Why? Because droplets that are left on the coil evaporate and go right back into the air in your home! 3 Signs of an Oversized Air Conditioner 1. Short Cycles The reason why oversized air conditioners don’t work as well is that they are able to meet the “cooling load” of the home sooner, and don’t cycle as long. When you have an oversized air conditioner, it can turn off before cooling as large a volume of air as a unit with longer cycles. A system that is too large will run in cycles of 8-10 minutes. The unit will quickly cool the air around the location of the thermostat, especially if the thermostat is close to the air handler. This causes the system to shut off without running long enough to cool the furthest rooms in the house. Not only will oversized air conditioners have short cycles, but the cycles will be frequent. When only some of the air in your home is 75F, and other areas of the home are left at 80F the overall temperature of the house will rise much faster than if the unit had cycled long enough to cool the entire space to 75F. 2. High Humidity Levels Indoors Another side effect of an oversized air conditioner is that your house won’t be dehumidified. When your air conditioner is only cycling for a few minutes, that doesn’t give the unit enough time to remove the water vapor from the air. It takes a cycle between 20 and 30 minutes for any unit to be able to condition and dehumidify the air. 3. Increased Electricity Bills Think of your unit starting and stopping during short cycles like turning your car off at every red light. Inefficient and expensive, right? It takes the most energy to start mechanics in motion. Continuing the motion requires significantly less effort compared to starting something that is stopped. You’re paying for that extra run time when your air is cycling for 8 minutes several times per hour, instead of 20-30 minutes once per hour. Replace Oversized Air Conditioner in Central Florida Do you suspect that your air conditioning system is too large for your home? The HVAC professionals at Energy Air are here to help! We offer free in-home consultations where we will identify the cause of issues with your HVAC system. It’s our zero-pressure way of creating a comfort solution that meets your home’s unique needs. If you’re ready to get started, contact us today or schedule your free estimate online.