One of the exciting new developments in heating and cooling over the last few years is the increased availability of inverter technology. As ACHR News reported in 2015, inverter technology used to be found only in ductless HVAC units, but in recent years has become available in some central air conditioning and heat pump units as well. The increased availability of inverter technology has homeowners wondering both what it is and what benefits it can offer for their homes and families.

What is Inverter Technology?

When people use the phrase “inverter technology” in reference to HVAC, they’re generally talking about an inverter-driven compressor.

• An inverter is part of the electrical components of an air conditioner or heat pump.
• It controls and modulates the electrical current running into the compressor’s motor.
• What this means in functional terms is that the inverter can adjust the speed at which the motor runs.

          This is different from a traditional HVAC compressor because without an inverter, the compressor only has two speeds—on and off. When the traditional compressor is switched on, it runs at 100% until it switches off again. You can think of a traditional compressor vs. an inverter-driven compressor as being analogous to a light that’s controlled by a switch vs. a light that’s controlled by a dimmer.

          Depending on the need, a compressor with inverter-technology can run at a wide range of speeds—in fact, it can even run higher than its standard “100%” speed for short times when necessary for extreme cooling. This change in compressor speed essentially changes the cooling/heating capacity of the air conditioner or heat pump. In other words, instead of acting as a 2.5 ton unit all of the time, it can act as a 1 ton unit or a 2 ton unit or briefly as a 2.7 ton unit, all depending on the need.

See Also: Carrier Ductless System with Inverter Technology

What are the Benefits of Inverter Technology?

          Now that you know what inverter technology is, let’s talk about why an air conditioner or heat pump with inverter technology might be right for your home. As ACHR News goes on to explain, the benefits of inverter technology are that it increases efficiency, decreases noise, and makes your home more comfortable.

Inverter Technology Increases Efficiency

          To understand how inverter technology saves energy, first think about how a standard air conditioner works. When the temperature in your home gets higher than the setting on your thermostat, the standard air conditioner switches on, its compressor running at 100% capacity. This brings down the temperature in your home, and the air conditioner switches off. The temperature goes back up, and the air conditioner switches on again, repeating the cycle. This can occur anywhere from 4-6 times per hour.

          The problem is that every time the air conditioner switches on, it uses a big jolt of energy to get the compressor motor going instantly from 0 to 100%. It’s sort of like how you’d be wasting a lot of gas if you turned your car’s engine off and back on at every stoplight. As Appliance Design magazine explains, inverter technology saves energy by:

1. Allowing the compressor to gradually ramp up to only the speed needed.
2. Instead of running full blast for a short time, turning off, and then repeating the cycle, the AC with inverter technology runs at a lower capacity for longer periods, decreasing the number of starts and stops.
3. The result is that inverter technology can reduce the amount of energy used by an air conditioner or heat pump by 30-50%.
4. Considering that heating and cooling costs make up fifty percent of the average household’s energy bills, that can add up to major savings. This potential for high efficiency explains why inverter technology is found in high-efficiency ductless units made by Daikin, as well as Amana’s top of the line 24 SEER central air conditioner and 20 SEER heat pump.

See Also: Common Summer HVAC Problems

Inverter Technology Decreases Noise

          Another benefit of inverter technology is that it decreases the noise produced by air conditioners and heat pumps. First, because the compressor ramps up gradually and only to the minimum necessary speed, it reduces the sudden change in noise levels from the HVAC starting up. Second, the noise during running is reduced whenever the compressor is running at less than 100% capacity. Essentially, you get more consistent, lower noise levels, which are less noticeable and bothersome than the dramatic on-off changes in sound level from a traditional unit.

See Also: Is My HVAC Too Noisy?

Inverter Technology Improves Comfort

• Instead of allowing the temperature of your home to swing up and down, an air conditioner or heat pump with inverter technology keeps the temperature steady.
• The inverter calculates exactly what speed is needed to keep your home at the temperature you’ve set and holds it there.
• Inverter technology also improves comfort by better controlling the humidity level of your home.

          As Appliance Design magazine explains, in hot, humid climates like we have in the Tennessee Valley, homes often have too-high humidity, which makes them uncomfortable. Air conditioners cool homes and also reduce their humidity, but if the air conditioner only runs for a short time, it can’t reduce the humidity enough. The longer run-times of air conditioners with inverter technology makes them better at taking humidity out of the air.