LG now making inverter window A/C's.

[Brian26]

Looks like the mini split inverter technology is now available in a window unit. LG is offering the first window inverter for sale in the U.S. Not a bad price at $469 either. The EER is significantly higher than a traditional window unit. They are claiming a 25-40 percent energy reduction compared to a standard window unit.

https://www.digitaltrends.com/home/lg-smart-ac/

https://www.lg.com/us/air-conditioners/lg-LW1517IVSM

 

[mnowaczyk]

They claim that starting the compressor sucks a lot of power, which is indeed true, but compressors are in use in all refrigeration. LG makes refrigerators. Whole house AC, industrial refrigeration units. They all use compressors to compress a refrigerant (which makes it hot) before sending it to a coil where the compressed refrigerant is cooled before hitting the expansion valve where it sucks up heat (gets cold) due to the expansion. That’s when air is blown across the cold coils before the refrigerant flows back to the compressor.

If a unit is sized properly, the compressor will run constantly on the hottest days. So it’s really the fringe cooling, or improperly sized units that will do the most stopping and starting. Perhaps this is most applicable to window units that are probably very often over sized for their application.

I had an oversized window unit that would freeze out our dining room in seconds, and as a result, it did a terrible job cooling our house. Maybe this LG technology would have been perfect for that application.

But why isn’t this Technolgy used in refrigerators? They should have fairly consistent load, with the exception of when the door is left open or it is loaded with hot food. Or is the technology already in use in other applications?

 

[peakbagger]

Inverter based refrigerators are sold in other parts of the world. They add cost so generally nor sold in areas with cheap power.like the US. They are more efficient and in theory should have longer life. Less surge load when the compressor cycles. I believe inverter based units are sold in Mexico.

 

[Highbeam]

But why isn’t this Technolgy used in refrigerators? They should have fairly consistent load, with the exception of when the door is left open or it is loaded with hot food. Or is the technology already in use in other applications?

Because it's an inverter with variable output a lack of consistent load is not a problem. The thing should be able to ramp up and down to maintain setpoint. Refrigeration is such a very small consumer of power. Like picking up pennies from the ground.

 

[maple1]

Now if only someone would make one that could heat too. That should be a goldmine, as long as they get it reliable.

 

[peakbagger]

They do make window units that heat, but they only go down to around 40 degrees. The big trick is to put an inverter compressor in window unit so it works down at lower temps.

 

[Brian26]

Here is a good graph on my mini split inverter electrical load. Mine will usually start out at min capacity and slowly ramp up.

I imagine a window inverter would be similiar. There is no high compressor start up load. It barely ever cycles completely off It just throttles back down to a min load. The savings on power and compressor life are huge.

Even when forcing 100 output using the turbo mode it still starts at min capacity and ramps up to full in about 5-10 mins. The compressor is essentially always throttled up from its lowest output.

 

[EatenByLimestone]

They are still too big. I cool my house with 2 6000btu and 2 5000btu window units. I like the quiet ratings though!


Opening the windows at night and shutting them during the day traps the cool air in.