Whether your existing AC is in need of upkeep or you’re in the market for a new one, read on for tips to stay cool.

Friendly American Standard HVAC technician, who is wearing a cap, smiles, holds a clipboard, and stands beside a condenser unit
A heating and cooling specialist should check your air conditioner at least twice a year.

Maintain AC Units for Maximum Performance

First, let’s talk about maintenance. While many homeowners have an air conditioner, they don’t necessarily know the ins and outs of performing regular maintenance on it.

Why is regular AC maintenance important? By maintaining the system, you will extend the life of the unit, and your home will remain at a comfortable temperature without an uncomfortably high energy bill.

How to Maintain Window, Portable, and Wall AC Units

If you have window units, the most important maintenance step is to change the air filter regularly.

Most window units have a simple filter in the front grill area. Clean it once a month during cooling season and replace it if it has any holes or appears worn.

Also, clean the air conditioner properly by vacuuming around it to remove any dust and dirt that can clog up the unit and cause it to malfunction.

During the off-season, take the unit out of the window and store it in a dry location. If you must keep the unit in the window, cover the part that is exposed to the outside.

How to Maintain Central AC Units

For central air conditioning units, the best way to keep yours working properly is to have it serviced bi-annually by a trained HVAC professional. They will take care of the many items related to maintaining the unit and be able to perform any necessary repairs or “tune-ups”.

Beyond that, keep the unit outside free from leaves and debris by raking around it and spraying off the unit with water. And make sure, above all, to change the air filter inside the house every few months or more.

For more information, read: 5 Easy Air Conditioner Maintenance Tips

    Woman controls mini split air conditioner with her remote control in a white room
    A mini split air conditioner pairs an overhead, remote-controlled system with an outdoor condenser unit. (DepositPhotos)

    Choosing a New Air Conditioner

    If your air conditioner is more than 15 years old, it may be time to purchase a new system. Do a little homework to get the best AC brand and unit type for your needs and keep energy costs to a minimum.

    There are various types of units to choose from including window, portable, through-the-wall, and central.

    Here’s a quick rundown of each type.

    Friendly American Standard HVAC technician, who is wearing a cap, smiles, holds a clipboard, and stands beside a condenser unit
    Central air conditioning is a popular choice, but matching the right-size unit with your home is crucial.

    Central Air Conditioners

    When it comes to choosing a central air conditioner, there are many factors involved, such as the size of your home, its number of windows and the amount of insulation.

    Air conditioning contractors can determine the correct system for your home. To choose one, check references, ask questions about warranties (limited vs. extended), and get several bids.

    Once you’ve selected a contractor, they will determine the correct size and type of system for your home.

    You might hear these terms when buying an air conditioner:

    • Seasonal Energy-Efficiency Ratio: This rates how many British thermal units an air-conditioner will remove for each watt of electricity consumed. The higher the SEER, the less you will spend on operating costs. Federal law mandates a minimum SEER of 13 for all new air-conditioning units.
    • AC Tonnage: A cooling ton in an air conditioner equals 12,000 BTUs per hour. That means a three-ton air conditioner can remove about 36,000 BTUs of heat per hour from your home.
    • Annual Fuel Utilization Efficiency (AFUE): This estimates how much heat a unit delivers for every dollar spent on fuel. The higher the AFUE, the lower your heating bills.
    Window air conditioner unit mounted directly in a window.
    A window air conditioner unit mounts right on the window. (©tanvirshafi, Adobe Stock Photos)

    Window Units

    When choosing a window unit, the most important factor is the size of the room you wish to cool and the cooling power, measured in British thermal units, of the unit you choose.

    Here’s a general guide for window air conditioners based on room size:

    • 12′ x 12′ room: 5,000 BTU unit
    • 16′ x 16′ room: 7,000 BTU unit
    • 20′ x 20′ room: 10,000 BTU unit
    • 24′ x 24′ room: 14,000 BTU unit

    In addition to size, make sure the AC unit you buy:

    • Has an EER (Energy Efficiency Ratio) of 11 or higher
    • Carries the EnergyStar label
    • Has a low noise rating
    • Provides good airflow
    • Uses a permanent or reusable air filter
    • Has various speed settings

    Related: How Much Does It Cost To Run A 8000 BTU Air Conditioner?

    Portable, ventless air conditioner rolled up beside a bed with a spread hanging down and tassels touching the hardwood floor.
    Portable air conditioning provides a zoned, efficient option for cooling small spaces. (©Axel Bueckert, Adobe Stock Photos)

    Portable AC Units

    A portable air conditioner is basically AC on wheels. It has an exhaust tube, which must be vented outside, to remove hot air from the room.

    Portable AC systems don’t require permanent installation. In fact, they come with wheels so can move them from room to room. And most of them come with a window venting kit that allows you to prepare a window for the exhaust tube.

    These systems accumulate moisture, and you’ll need to routinely drain them. This means emptying a reservoir on the unit or hooking up a drainage hose, if compatible with the unit.

    Before purchasing a portable AC, consider its energy efficiency. Systems with dual hoses cool rooms faster than their single-hose counterparts.

    Read also: What is a Floor Air Conditioner?

    Through-the-wall air conditioner unit, as seen in a luxury hotel room
    Through-the-wall air conditioners (which are exactly what they sound like) are commonly found in hotel rooms, but you also can purchase them for the home. (DepositPhotos)

    Through-the-Wall Units

    You often see through-the-wall AC units in hotel rooms, but they’re also ideal for large open rooms, studio apartments or remodeled garages.

    You can use through-the-wall units in rooms that aren’t connected to a central air conditioning system. They’re ideal for home additions and, really, wherever you want to add AC without running ductwork.

    You can purchase these units with heating and cooling features, or just cooling features, and you must carefully choose where to install them.

    You must install these units in exterior walls where there’s no plumbing or electrical wiring. In addition, you’ll need to install a sleeve or chassis that can support the weight of the air conditioner.

    A mini-split ductless air conditioner is one type of through-the-wall system, but it’s not boxy and comes with a separate outdoor unit. Mini-split AC units are sleek, subtle and look good in any home. If you are interested in this type of AC, take a look at our ductless AC unit cost guide.

    Consider A Warranty

    If you’ve ever been curious about what a home warranty entails, here it is: A home warranty plan safeguards the appliances and essential systems within your residence, encompassing major home appliances, electrical components, plumbing, and HVAC systems. In contrast to your homeowners insurance policy, which provides coverage for specific perils, a home warranty operates as a service agreement that addresses the effects of regular wear and tear.

    So, If you are worried about your air conditioning unit breaking down due to normal wear and tear, consider investing in a homeowner’s warranty.

    A review team independent of Today’s Homeowner picked out the best homeowner warranty providers, though they also looked at smaller companies such as Fidelity National Home Warranty, Global Home USA Warranty, and A.B. May Home Warranty.

    Further Information

    Editorial Contributors
    avatar for Danny Lipford

    Danny Lipford


    Danny Lipford is a home improvement expert and television personality who started his remodeling business, Lipford Construction, at the age of 21 in Mobile, Alabama. He gained national recognition as the host of the nationally syndicated television show, Today's Homeowner with Danny Lipford, which started as a small cable show in Mobile. Danny's expertise in home improvement has also led him to be a contributor to popular magazines and websites and the go-to source for advice on everything related to the home. He has made over 200 national television appearances and served as the home improvement expert for CBS's The Early Show and The Weather Channel for over a decade. Danny is also the founder of 3 Echoes Content Studio, TodaysHomeowner.com, and Checking In With Chelsea, a décor and lifestyle blog.

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