First of all, there is no “best” air conditioner. The best AC for you depends on your budget, your interest in energy savings and consumption, and the configuration of your home.

There are 6 options for cooling your home. Here they are in descending order of popularity in the Greater Boston area:

• Central Air Conditioners
• Ductless Mini-Splits
• Window Units
• Portable Units
• Hybrid Air Conditioners
• Geothermal

Central Air

This method of cooling uses one large outdoor unit to push cold air into a whole building through ducts and vents. Modern central AC is energy-efficient, and may have HEPA filters built in to keep your air clean. This type of cooling is much quieter than individual window units, and is virtually invisible (inside the house, at least). However, central AC demands a huge upfront cost, putting it out of reach for many homeowners. It also needs regular maintenance and changing of filters, and the outdoor unit is large and unsightly. Its biggest con, however, is that if you don’t already have a duct system in place, central air is basically a non-starter for you: installing the ducts and vents is massively disruptive and incredibly costly. 

Mini Splits

These seem to be getting installed everywhere in our neighborhoods; I have them, as do Liz and Ellie! Mini splits use an outdoor base unit, then run the cool air through ducts outside the home and into your rooms via a slim unit. The indoor piece can be mounted on an indoor wall, leaving your windows unobstructed. If you want more options, some have a heat pump in addition to cooling capability. Mini-splits are whisper-quiet, and cost less to operate than central air conditioning. Finally, with our older homes using radiators or baseboard forced water as opposed to forced air (which has ducts that central air could use), these are a good substitute for central air. However, the upfront cost can be as high (or in some cases, higher) than central air. The large unit must be outside, and it’s not the prettiest thing you’ve ever seen. Mini splits need maintenance such as filter changes and refrigerant top-offs, as well. And this one may be a pro or con depending on your preference, but each unit must be operated independently of the others; you can’t just set it and forget it!

Window Units

Since Boston’s homes tend to be on the older side, many homeowners and landlords choose window AC units. According to Consumer Reports, LG’s units seem to be the big winners: “LG now tops our tests in all three sizes of window ACs we test—small, midsized, and large.” There’s even an option for a U-shaped window AC that is quieter and more efficient than the traditional design. Here it is on Amazon.  Friends and clients who have them seem to love them! If you prefer to buy in person, the best time to buy an air conditioner is in the fall (of course), as companies are trying to get rid of their stock.There are certainly drawbacks to window units, including aesthetics: if you have a unit in every room of your home, you’re blocking the light out of each window with a big, clunky, loud piece of metal. There’s also the need to match the power of the AC unit to the size of the room; a large room with a too-small AC will simply never get cool enough. And although newer ACs are more energy efficient these days, they’re still pretty inefficient overall.

Portable Air Conditioning Units

A portable air conditioner is a self-contained cooling unit designed to provide temporary or supplemental cooling in a specific area or room. Unlike central air conditioning systems, portable AC units do not require permanent installation or ductwork. They typically consist of a compact, wheeled unit that houses components such as a compressor, evaporator, condenser, and fan. Portable air conditioners work by pulling heat and humidity from the air in the room, cooling that air down, and then expelling the heat through an exhaust hose that needs to be vented through a window or a specially designed vent. These units are great for apartment owners who only need cooling seasonally, for example. They’re fairly easy to install (you will need a venting kit for the hot air), and are much less expensive than central air or mini splits. And, being “portable,” you can just roll them from room to room as needed! They do tend to be less energy efficient, though, since they struggle to cool large areas. And these units are large, so if you have limited floor space, you may want to go with window units instead. Portable units are definitely noisy, as well. 

Hybrids

Hybrid air conditioners, also known as dual-fuel or hybrid heat pump systems, offer a combination of electric cooling and gas heating. The pros include energy efficiency, cost savings, and year-round comfort. These systems automatically switch between electric cooling and gas heating based on outdoor temperatures, which optimizes efficiency. However, hybrid air conditioners usually have higher upfront costs compared to standalone cooling or heating units. They also require access to a natural gas supply, limiting their availability in certain areas or households without gas connections. Regular maintenance is necessary to ensure proper functioning of both electric and gas components.

Geothermal

Geothermal cooling, also known as geothermal air conditioning, uses the Earth's natural heat exchange process to provide cooling for buildings. It relies on geothermal heat pumps (GHPs) to transfer heat from the interior of a building to the cooler ground or groundwater. The pros include high energy efficiency, reduced operating costs, and minimal environmental impact. In addition, geothermal systems can provide both cooling and heating, offering year-round comfort. They have a longer lifespan than traditional cooling systems and require less maintenance. However, geothermal cooling has high upfront installation costs and may even require drilling or excavation. It also requires sufficient land space for the installation of ground loops or wells, limiting its feasibility in urban areas or smaller properties.

If you've gotten this far, you really care about how you cool your home. You may also be interested in signing up for alerts from the Green Energy Consumer Alliance.  On the hottest days of the year, energy use spikes, forcing power companies to burn the dirtiest of fuels to keep the electricity coming. Consider signing up to #shavethepeak to get alerts about high-energy usage days and commit to lowering your electricity usage, thus lessening the necessity to burn the most polluting of fossil fuels.

Which air conditioning solution fits your home’s style and age, as well as your budget and personal preferences? We recommend that you consult with HVAC professionals, particularly if you’re not leaning towards window or portable AC units; they can help you weigh your options and decide on the best fit for you. Need a recommendation for an expert? Ask us! We’re here to help.