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Air Conditioner Inverter Review - Many mini-split air conditioners and heat pumps use inverters for efficiency. Conventional split system air conditioners and heat pumps can now be purchased with inverters for ultra-efficient heating and cooling.
Inverter air conditioners came to the USA in the form of ductless mini-split air conditioners. They were later expanded to ductless mini-split heat pumps. Inverter air conditioners and inverter heat pumps are considered the most efficient systems available on the market. This is true for conventional systems as well. That includes air source air conditioners and air-source heat pumps. Finally, inverter air conditioners and inverter heat pumps come close to matching the efficiency of geothermal heat pump systems.
In fact, some inverter air conditioners and inverter heat pumps beat some geothermal heat pump systems. That is when matched up for efficiency. If it is impractical to drill a well or do trenching for a geothermal system and you want very high efficiency the next best thing is an inverter air conditioner or an inverter heat pump.
Of course, with an air source heat pump, geographical considerations must take precedence as air source heat pumps are not practical in the northern climates for technical reasons unless they are specially engineered heat pumps for operation in the Northern climate region.
Inverter Air Conditioner Review Efficiency Ratings
To compare a conventional split system air conditioner or heat pump with an inverter air conditioner or heat pump I’ll use an analogy to help you understand how inverter air conditioners and inverter heat pumps are far more efficient than conventional split system air conditioners or heat pumps. First, we have the conventional air conditioner or heat pump that will cycle on and off 4 to 7 times an hour on a hot day.
When the conventional air conditioner or heat pump starts it uses a tremendous amount of power to get started as it was at a dead stop and needs to get to full blast in a split second. That’s a lot of inrush current the unit is consuming just getting started. Then it will run at 100 percent throughout the cycle until the thermostat is satisfied and then the air conditioner or heat pump shuts down only to begin this vicious cycle over and over again throughout the day and into the night as long as the house is hot.
That is how conventional heat pump and air conditioner systems work. It seems like an inefficient way to do things but it is how it works. Technology is slowly changing all that.
In comparison, the inverter air conditioner chugs along at the absolute minimum required to cool or heat (depending on the mode of operation) and it is likely the inverter air conditioner or inverter heat pump will continue to run all day long never shutting down until the ambient temperature outdoors falls.
Air Conditioner Inverter Review | Comparisons
Comparing the two, it is akin to two cars in the city. The inverter car has a dedicated lane and never has to stop at stoplights or stop signs. The conventional car is in another lane and must stop at all stoplights and stop signs. The conventional when it starts it goes from 0 to 100% in a split second. Then it has to have to come to a screeching halt at the next light.
The inverter car is chugging along in the dedicated lane. It rarely stops only using enough energy to keep the pace. It keeps up with demand so if it gets really hot outside it will run at 100%. However, if it is not so hot outside it will run at say 30% to keep the space comfortable. This saves a lot of energy. This is especially true if you factor in that there are more days when you only need the air conditioner to run at 50% instead of what the conventional air conditioner will always run at 100%.
Air Conditioner Inverter Review Comparison to Geothermal
Taking into account all the costs of installing a geothermal heat pump system including drilling a well or digging multiple trenches, the inverter duty air conditioning system offers a great value with an excellent efficiency that can only be beaten with the top of the line geothermal systems. There are some conventional air conditioners and heat pumps with high-efficiency ratings. However, these are not inverter-duty air conditioners. Rather, they rely on staging to achieve high efficiency. Many manufacturers use a two-stage scroll compressor for this type of system.
To do this, the conventional air conditioner or heat pump needs either a compressor that can shift stages from 100% to lower capacity, or the conventional air conditioner or conventional heat pump has two compressors for staging. Conventional HVAC systems with two compressors have one small compressor for light loads and a large compressor to run at 100% when demand is high. A small list of manufacturers now offering inverter duty air conditioner and heat pumps include:
- Daikin Air Conditioners and Daikin Heat Pumps
- Maytag Air Conditioners and Maytag Heat Pumps
- Lennox Air Conditioners and Lennox Heat Pumps
- Carrier Air Conditioners and Carrier Heat Pumps
- Trane Air Conditioners and Trane Heat Pumps
- Rheem Air Conditioners and Rheem Heat Pumps
Air Conditioner Inverter Review | Compressors
The inverter air conditioner or inverter heat pump has one compressor (rotary compressor) that is controlled by a microprocessor. The microprocessor receives its input from various sources including the room thermostat. It also receives input from other components in the system that have the ability to measure load. The important part of an inverter air conditioner or an inverter heat pump is measuring the load. This way, the microprocessor can control the compressor and other components. That specific gives the appropriate output to keep the demand satisfied.
Because the inverter air conditioner or inverter heat pump only runs at the necessary speed to keep up with the demand, the units are typically ultra-quiet. You will likely not even know they are running, especially the outdoor unit. In conventional air conditioners and heat pumps, noise is a big nuisance. Especially for many outdoor condensing units. Therefore, the inverter air conditioner and the inverter heat pump can usually beat the conventional system. That is when it comes to lower decibel levels with both the inside and outside units.
Air Conditioner Inverter Review Conclusion
Matching the systems up side by side from the conventional system to the inverter system, the inverter systems beat the conventional system hands down. Some of the inverter air conditioner and inverter heat pumps available are ductless. However, there are ducted inverter air conditioners available also. (see the list above). Some of the names for the ductless air conditioners and heat pumps include:
- Daikin Mini-split Air Conditioners and Daikin mini-split Heat Pumps
- Mitsubishi Mini-split air conditioners and heat pumps
- Fujitsu mini-split air conditioners and heat pumps
- LG mini-split air conditioner and heat pumps
- Samsung mini-split air conditioner and heat pumps
Air Conditioner Inverter Review | Conclusion
Currently, some manufacturers have inverter duty compressors. That is the standard heating and cooling equipment that modulate from a low percentage to 100 percent of capacity. (See the list above). That has been a long time coming. However, it’s here now, and the efficiency ratings of these types of systems have gone through the roof. The only thing prohibitive about these types of systems is the costs of installation.
These systems are not cheap. However, over the long term, they do save tons of money on your power bill — savings for both heating and cooling (for those with heat pumps).
Good luck, and we hope you find the right system! Get a system that will serve all your heating and cooling HVAC needs and do so efficiently. If you have any questions, don’t hesitate to email us and mention the question for Mr. HVAC on the subject.
Air Conditioner Inverter Review
Great article. I’m replacing a 1.5 ton GE Zoneline heat pump with a floor console mini split HVAC inverter heat pump. I plan to install it in the existing opening and want a very quiet, efficient unit.
1. Are the condenser and evaporator fans also inverter controlled?
2. Since I cannot select a unit for the exact heat/cooling loads, is it best to oversize or undersize the unit and why? I’m confused since I’ve read recommendations both ways.
If its invertor duty it is usually quiet. I say usually because Ive seen a few that are not. Good installation practices helps. If you cant get the tonnage to match the load calculation slightly undersized is better than oversized IMO.
The knowledge of this site is very impressive. You have helped make this a seamless learning experience for me as I read about information on AC units. Thanks for all the information.
Great post! I was looking for something to educate some customers of mine about the value of inverters for heat pumps and a/c. That analogy of the slow car that never has to stop compared to the car with all the stoplights, is golden. Glad I found this site! Thanks.