Air conditioners are measured in a variety of ways. There’s horsepower, BTU, amps and wattage, among other information on the sticker. When it comes to efficiency however, AC units are measured by two universal standards: EER and SEER.
What are they, and how do they factor when shopping for an air conditioner unit?
As winter gives way to spring, the melting snow can wreak havoc on two particularly vulnerable areas of your home: the roof, and the basement.
Ductless mini splits are a great way to heat and cool indoor spaces without the mess and complications of traditional HVAC systems. For most mini splits, installation only requires a small hole to pass the power, refrigerant, and condensation line between the indoor and outdoor unit.
However, mini splits can also cost a pretty penny in utilities, particularly multi-zone units that heat and cool multiple rooms. Thankfully, homeowners can cut down those dreaded monthly bills with mini split inverters.
A mini split AC unit has the same function as other air conditioners: cooling your home. The main difference is that mini split air conditioners do not rely on ducts, which is why they are also referred to as “ductless air conditioners.”
The cooling (or heating) process happens via two components: an indoor and an outdoor unit. The indoor unit blows the warm air over cold evaporator coils containing refrigerant, which absorbs that heat from the air, and runs it to the outside unit. Through the compressor, the refrigerant dumps the heat pulled from your home’s air.
Within the mini split systems, there are two types of compressors: rotary and inverter.
A rotary compressor runs on a fixed capacity, while a mini split inverter uses only enough power to reach and maintain your set temperature, and then idles at that setting until more power is needed. This results in more efficient operation.
For a more detailed explanation, see our entry What is a Mini Split Inverter?
Reduced power consumption
Longer operational lifespan
Faster cooling
Long-term savings
Single-zone mini-split inverter:
One of the main features of Panasonic’s ClimaPure XE series is the company’s Nanoe X Technology, a patented system designed specifically in the age of Covid. It uses nano-sized electrostatic atomized water particles rich in hydroxyl (OH) radicals to reduce pollutants and odors, including airborne viruses. It was found 8 hours of operation resulted in 91.4% effectiveness at eliminating the Novel Coronavirus, while 24 hours of operation recorded a 99.7% effectiveness rate.
The NanoEx technology boasts no less than seven purifying effects, which include deodorizing, the ability to inhibit 5 pollutants for a more comfortable environment, and the ability to help keep your hair and skin moisturized. The five pollutants filtered by NanoEx include bacteria and viruses, mold, allergens, pollen and hazardous substances. Not only are you and your family protected from these pollutants and odors, but your clothing and other stored items may also be protected.
The ClimaPure series also offers a host of other features, including low ambient operation down to -0°F, heating capabilities down to -15°F, and built-in WiFi that allows users to control the unit from from anywhere with an internet connection.
Panasonic proudly introduces the new ClimaPure XE mini-split systems for cold climates! The ClimaPure Series includes many new features that n...
Panasonic XE9WKUA 9000 BTU ClimaPure XE Series Single Zone 28.1 SEER Heat Pump System - Built-In WiFi - Energy Star
Dual-zone mini-split inverter system:
GE ASH220NCDWA 20,000 BTU Configurable 2 Zone Mini-Split Air Conditioner with Heat Pump – Energy Star
This dual-zone mini split is an 18,000 BTU AC with heat pump that supports two zones, meaning it can support two indoor units in separate areas of your home. The unit offers a combined connectivity capacity of up to 24,000 BTUs – with a cooling capacity that ranges from 7,000 – 20,000 BTUs. Its cooling mode can handle outside temperatures as low as 0°F and as high as 115°F.
Standard features include a quiet, energy efficient variable speed inverter compressor; blue fin technology to ensure the condensate does not sit in the condenser for improved rust prevention and longer operating life; and a warm start function that delays the fan until the air is warm enough, to stop cool drafts.
This outdoor unit can be paired with three choices of GE Standard Wall Units (ASYW07URDWA, ASYW09URDWA, ASYW12URDWA), or two choices of Ceiling Cassette Units (AB09SC2VHA, AB12SC2VHA).
Base Price shown is for outdoor unit only. You can choose up to 2 indoor units below with a total connected capacity of 24,000 BTUs. The price display...
GE ASH220NCDWA 20,000 BTU Configurable 2 Zone Mini-Split Air Conditioner with Heat Pump - Energy Star
Multi-zone mini-split inverter:
This 34,000 BTU multi-zone cooling and heating system has enough grunt to power most residential homes and even retail businesses. LG’s Flex Quad Zone Multi-Split air conditioner lets you install up to four indoor units with a combined BTU rating of up to 48,000 BTUs of wall mounted or ceiling cassette indoor units.
The LMU36CHV outdoor unit offers a super energy efficient variable speed inverter compressor, defrost/deicing capabilities, three minute restart delay, and a self diagnosis system. It also includes soft start which reduces power surges on the electrical system. It operates when the outside temperature is as low as 14°F in the cooling mode and from -4°F to 64°F in the heating mode. To top it all off, it uses environmentally friendly R-410A refrigerant and is precharged for up to 98’ of line.
Base Price shown is for outdoor unit only. You can choose up to 4 indoor units below with a total connected capacity of 48,000 BTUs. The price display...
LG LMU36CHV 36,000 BTU 22 SEER Configurable Quad-Zone Mini-Split Air Conditioner with Heat Pump - Energy Star
Concealed duct mini split inverter:
Daikin FDXS09LVJU / RXS09LVJU 9000 BTU Class Slim Duct Ceiling LV Series Heat Pump Mini Split
This streamlined and slim unit offers 8,500 BTUs of cooling capacity and 10,000 BTUs heating. It will efficiently cool a room that is about 350 – 400 sq. ft. and boasts an EER of 11.2 and a SEER rating of 15.1, thanks to Daikin’s variable speed compressor technology.
Features include Econo and Stand-by modes, auto fan speed, night set mode, dry function, fan only and on/off timer. The heat pump also boasts auto changeover and hot start function, while the condenser has Anti-Corrosion Treatment to protect it from the elements.
Energy efficient, comfort control is yours with a Daikin LV Series single zone mini-split. This unit is a cooling system with a heat pump. Each singl...
Daikin FDXS09LVJU / RXS09LVJU 9000 BTU Class Slim Duct Ceiling LV Series Heat Pump Mini Split
Ceiling cassette mini split inverter:
Panasonic E12RB4U 11900 BTU Single Zone Ceiling Cassette System – Heat Pump
Ceiling cassette mini split systems are a great alternative when floor space is at a premium. This single zone mini split system consists of the indoor 4-Way Ceiling Cassette Unit (CS-E12RB4UW) and the CU-E12RB4U outdoor condenser, and CZ-BT20 decorative grille cover for the ceiling cassette.
The system boasts 11,900 BTUs of cooling power and 13,600 BTUs heat pump capacity, with a 18.0 SEER, and 10.30 EER ratings.
Features include Panasonic’s ECONAVI – Human Detection Technology, which adjusts the unit’s operation when it detects human activity or lack thereof in the space, as well as the airflow direction; Automatic Heat and Cool Changeover that kicks in when set temperatures are reached; built-in System Self Diagnosis, and automatic restart after power failure.
Panasonic's inverter provides maximum power control and highly efficient operation by modifying the power supply frequency. The result is fast, flex...
Panasonic E12RB4U 11900 BTU Single Zone Ceiling Cassette System - Heat Pump
For more recommended AC units, see our Top Air Conditioners for 2022 list.
Humidity is one of those things that few of us think about, yet play a vital role in our everyday lives. Humidity can affect health, comfort, allergies, and even physical structures.
When humidity levels get too high, they can lead to a sticky feeling, trigger allergy attacks, and have a detrimental effect on your house and furniture. This is particularly concerning during the warmer months, when humidity levels tend to be high.
A dehumidifier can help regulate indoor humidity levels and bring it back to a safe level.
During the summer, the ideal relative humidity (RH) level indoors is 50%. RH levels that that go beyond can have a detrimental effect, such as:
Human body
House
Furniture
A dehumidifier can prevent these effects by maintaining the right RH levels.
A dehumidifier is a device that is designed to remove excess moisture from the air. It does this by using a fan to force air through coils filled with coolant, thereby sucking moisture from the surrounding air and turning it into water that can be collected and disposed of. The resulting dry air is then circulated around the room or house.
There are two methods of dehumidification:
Condensate dehumidifiers – these use a miniaturized refrigerator to collect the condensate. These are typically found in larger dehumidifiers.
Desiccant / absorption dehumidifiers – these use hydrophilic materials like silica gel contained in a cartridge to suck the moisture from the air.
As its name suggests, this humidifier uses an exhaust fan to expel air outside. A sensor detects the humidity levels and regulates the moisture by forcing air out. They are often used in basements, attics, and crawl spaces.
Also known as desiccant dehumidifiers, they use hydrophilic materials to bond with the moisture in the air. The hydrophilic material is often contained in a cartridge that can be refreshed and disposed of as necessary.
Commonly found, these use a fan and heat pump to remove the moisture. The fan forces air through heat exchanger coils to suck out the moisture and turn it into condensate, which is then collected into a drip compartment or pumped away. Because of their larger size and complexity, they are more expensive than absorbent dehumidifiers, but do not require cartridges.
Unlike most home appliances, a dehumidifier’s function is simple enough that it can be copied via DIY. These can range from simple absorbers like rock salts and silica gel placed in the room to more elaborate devices that use fans combined with damp meters or hygrometers to measure the humidity level in the room.
| Type | Cost | Ideal Use |
| Dehumidifying Ventilator | Medium (requires installation) | Basements, attics, crawlspaces |
| Chemical Absorbent Dehumidifier | Low | Single rooms |
| Heat Pump Dehumidifier | Medium (may be high for units that require installation) | Single rooms, Basements, Whole house or larger spaces |
| DIY Dehumidifier | Low (depending on design and complexity) | Smaller spaces or barely used rooms |
Portable Dehumidifiers
Budget option:
Danby DDR022BJWDB 22 Pint Portable Dehumidifier with Direct Drain Option – Energy Star
This portable dehumidifier can remove up to 22 pints (10.4 liters) of moisture per 24 hours, up to about 1,500 sq. ft. of space. Features include a “bucket full” light; an auto-de-icer that prevents ice build-up on coils; and a Smart Dehumidify Function, where it automatically regulates the room humidity by factoring in the ambient temperature.
The unit is Energy Star compliant and has an LED display with electronic controls for easy operation.
The Danby DDR020BJWDB portable dehumidifier removes up to 22 pints (10.4 liters) of moisture per 24 hours, protecting your home form unwanted humidity...
Danby DDR022BJWDB 22 Pint Portable Dehumidifier with Direct Drain Option - Energy Star
Premium model:
Friedrich D50B1A 50 Pint Portable Dehumidifier – Energy Star
This unit is perfect for large wet to very wet spaces ranging from 1000 – 2000 sq. ft., such as areas with standing water or always wet floors. It can remove up to 50 pints of moisture from the air in a 24-hour period.
Features include a 2-speed fan, auto defrost that works as low as 41°F, and a digital touch panel. It includes a slide-out washable filter and roll casters for convenient movement.
The D50B1A provides three drainage options: a removable 16 pint collection bucket with handle for manual emptying, a continuous drainage setup, or the included drain pump that can be positioned vertically or horizontally up to 15 ft. from the unit.
Friedrich Room Air Conditioner 2022 Rebate
The Friedrich D50B1A 50 pint dehumidifier is perfect for larger wet to very wet spaces from 1000 - 2000 sq...
Friedrich D50B1A 50 Pint Portable Dehumidifier - Energy Star
Standalone Dehumidifiers
Crawlspace dehumidifier:
Seaira WatchDog NXT60 Crawl Space Dehumidifier
One of our most compact standalone units, the Seaira WatchDog NXT60 is a small dehumidifier that fits smaller budgets. But don’t let its small size and price tag fool you: this little unit is capable of servicing up to 11,000 cubic feet of space and produces 155 CFM airflow, making it perfect for crawlspaces.
The NXT60 can operate in a wide range of temperatures from 33°F – 105°F, and Operating Relative Humidity Levels from 36% – 90%. It has a rated Condensate Capacity of 60 pints per day (at 80°F and 60% RH). It is designs to be installed in a crawl space, near your sump pump or other drainage area for the gravity drain system to function properly. As such, a 12″ drain line comes standard. The unit must be elevated to some degree to allow for water to flow through the gravity drain and requires a 115V, 3 prong GFI outlet with a 15 amp time delay fuse.
Small enough to fit in almost any crawl space, the WatchDog NXT60 is one of the most compact dehumidifiers you can find. But don't let its size fool y...
Seaira WatchDog NXT60 60 Pints Per Day Crawl Space Dehumidifier
Whole House Dehumidifier:
Aprilaire E130 130 Pint E-Series Professional Grade-Whole House Dehumidifier
Aprilaire’s E-Series delivers professional grade dehumidification for your entire home. The E130 is an Energy Star Rated dehumidifier that is perfect for use in basements, crawl spaces or as a whole house dehumidifier. It can remove up to 130 pints of moisture per day, in up to 7,200 sq. ft. of space, making it perfect for larger homes and basements.
A blower inside the dehumidifier draws air in, filters the air and removes the moisture, then discharges the clean, dry air through your HVAC system or into a dedicated area of your home (such as the basement or crawl space). The condensed moisture is directed into the drain pan and then to a tube or hose that is routed to the floor drain or condensate pump (not included).
This premium unit was recognized as the Energy Star’s Most Efficient for 2021, and boasts corrosion-resistant aluminum coils that are made in the USA.
Good air is essential to a clean, comfortable, and healthy living environment. Aprilaire's E-Series delivers professional grade dehumidification for y...
Aprilaire E130 130 Pint E-Series Professional Grade-Whole House Dehumidifier - Energy Star
With the ever-rising prices of utilities, inverter air conditioners provide a cost-efficient way of cooling your home without breaking the bank. And LG’s line of inverter ACs combine the benefits of inverter technology with the expertise and durability of one of the world’s foremost appliance brands.
Conventional air conditioners run on a fixed capacity: they are either off (0%), or on (100%). This means it’s always running at its highest capacity, which makes it inefficient.
An inverter AC is able to adjust its output capacity to suit the cooling need. The inverter directs the compressor unit to either increase or decrease the output based on the room’s air temperature, instead of blasting away at full volume all the time.
Reduced power consumption
Longer operational lifespan
Faster cooling
More quiet
Long-term savings
LG’s line of inverter air conditioners combine inverter technology with a variable speed compressor. This adjusts the speed of the compressor motor to more accurately regulate room temperature compared to traditional air conditioners, which can only turn the compressor on or off.
The result is a quiet, more efficient, and longer lasting AC unit that also boasts higher energy savings. In fact, LG inverter air conditioners can save up to 70% more in energy consumption, based on testing by third-party laboratory Intertek on LG’s LA200WC AC model.
Compressors are one of the most critical elements of air conditioners. Unlike most other brands that outsource their compressors, LG manufacturers its own compressors in-house with LG’s very own parts.
Single-zone inverter mini-split:
LG’s HYV3 series of inverter ACs features low ambient heating operation down to -13°F, making these units a viable option as a primary heat source. This particular model is rated at 9,000 BTUs and can service a space up to about 375 sq. ft. It boasts a high efficiency rating of 27.5 SEER and an EER of 15.8, and HSPF rating of 13.5.
Apart from its impressive ratings, one of the upgraded features on the LA090HYV3 is built-in WiFi (previous HYV models required an optional module for WiFi) for smart home control. Also included is the ability to have more of a height differential between the indoor and outdoor units. The HYV3 allows for elevations up to 39.4 feet (vs. 32.8′).
The line is also available in 12,000, 15,000, 18,000 and 24,000 BTU models.
The HYV3 Series features low ambient heating operation down to -13°F making these units a viable option as a primary heat source! With a cooli...
LG LA090HYV3 9000 BTU 27.5 SEER Art Cool Premier Single Zone Mini Split System with Heat Pump and Built-In WiFi - Energy Star
Multi-zone inverter mini-split:
LG LMU180HV 18,000 BTU Configurable 2 Zone Mini-Split Air Conditioner with Heat Pump
LG’s Flex Multi-Split Dual Zone series allows you to install two indoor units in separate areas of your home. This 18,000 BTU mini split AC is a dual-zone air conditioning and heating system with a combined connectivity BTU rating of up to 24,000 and can be configured to include a combination total of 2 wall mounted and/or ceiling units. Whether connected with non-ducted, ducted units or a combination, the system maintains its Energy Star Qualification.
The Multi-F / Flex Systems are not only cost and energy efficient, they are also able to offer comfort year round with enhanced cooling and heating ranges. It is capable of heating when outdoor temperatures are as cold as -4°F, so it can function as a primary heating system in most parts of the country. Cooling-wise, it can operate in the cooling mode with outside temperatures as low as 14°F. With the addition of the optional drain pan heater (PQSH1203), the cooling operation can be enhanced to -4°F.
Each unit operates with its own remote or thermostat (depending on the units you choose), so there is no need to condition the room you are not using.
Base Price shown is for outdoor unit only. You can choose up to 2 indoor units below with a total connected capacity of 24,000 BTUs. The price display...
LG LMU180HV 18,000 BTU Configurable 2 Zone Mini-Split Air Conditioner with Heat Pump - Energy Star
Ceiling cassette inverter mini split:
LG LC128HV4 12,000 BTU Single Zone Ceiling Cassette Mini Split with Heat Pump
Ceiling cassette mini split systems are a great alternative when floor space is at a premium. The LC128HV4 Single Zone Mini Split System is a great option for colder climates, capable of operating in conditions down to -4°F in heating mode and down to 0°F in cooling mode. An optional wind baffle can further enhance the cooling operation down to -4°F.
This indoor unit boasts 11,100 BTUs of cooling power and 14,000 BTUs heat pump capacity when used with the compatible LUU127HV outdoor unit. It is Energy Star-qualified with 19.4 SEER, 12.6 EER and 10.4 HSPF ratings.
Features include Jet Cool mode, which operates the unit at high speed for up to 30 minutes to quickly cool a room down to 64°F; Swirl Wind, a four-way controlled louver and fan speed system that creates a stronger, wider air flow and reduces temperature stratification; and a Dehumidifying Mode that controls humidity by shutting down the compressor before the space gets over-cooled.
The LC128HV4 Single Zone Mini Split System is a great option for colder climates. This system will operate in cold conditions - down to -4°F in t...
LG LC128HV4 12,000 BTU Single Zone Ceiling Cassette Mini Split with Heat Pump 230 Volt - Energy Star
For more recommended AC units, check out our Top Air Conditioners list.