Finally an energy saving window unit built ! Wow

Dave Angelini

Finally an energy saving window unit built that requires little skill to install. Gamechanger from LG

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

just starting

Thanks Dave.

Dave Angelini

Enjoy !  Should be more of this coming from others. You can't go wrong with LG

WaterWheel

With a suggested price of $469 for a 14,000 unit it's a lot less expensive than the mini-split.       And at 44 db it's quiet too.

Dave Angelini

But not yet in the efficiency of the best splits. Still pretty darn nice with all of the bad parts of a window unit gone. A great spare also!

Nesto

Newbie here, after paying almost $500 per mo this past summer in electric bills to run the ac 12 hrs a day (can't afford a divorce), with the knowledge I gained from installing a 500 watt array (2x 250; 40 amp cc; 1k watt ps xantrex inv; 430 amp batteries) to run my pond pump & 400 watts of panels on my trailer (same  solar set up and runs a 10cuft frig and all led lights for 3 days)

I've been looking to run 3-4 split air units on panels (each independent) to cool part of my 2500 sq ft home here in so cal. Was just about to go for it when I ran across this article for window units and just about jumped out of my chair b/c of the simplicity to install vs split air.

My initial thinking is along the following lines: 4x300 watt panels; 40 amp cc, 1500 ps inverter,("x" hrs battery back up), to run the window units at 300 watts+/- first thing in the am until it really starts to heat up then increase to 800+/- watts until later afternoon then reduce to 300 watts then battery back up for 2-3 hours. I realize the solar array won't be able to run the LG 14000 btu full blast all day but at 300-800 watts for the entire day on solar which should keep house at a cool temp, even with 3-4 units, I'm thinking this will use a heck of a lot less electricity than what I'm using now with my central hvac unit especially since two bedrooms are now emptynesters.

Dave, any input or suggestions?   My back yard is  pretty big and have area to face some panels east/west and others right over pool equipment/bedroom deck, so have solar panel placement covered.

BB.

Nesto,

How is the insulation for your home? As I understand a large loss for central air is heat loss through the ducting... Mini-splits don't have ducting, so they can have improved efficiency over your present central A/C. And if you need some heat, mini-split heat pumps can help you there too. More efficient and less costly than baseboard electric heaters (if you have natural gas heating, a heat pump may not save much money over natural gas heating).

On the solar power question... Are you looking at Grid Tied solar power system (solar panels+GT inverter(s))? Or are you looking for a battery based system (hybrid/off grid solar power system)? In general, GT Solar is about the cheapest/most reliable system for generating power for your home--But the pendulum is swinging the other direction now and GT Solar power systems are losing their subsidies (rate plans that are very favorable to GT Solar installations).

Hybrid and off grid solar power systems (that have battery banks), tend to be much more expensive to install and maintain... And I would not suggest such a system to "save money".

-Bill

Dave Angelini

Bill is spot on.  I also think you are assuming alot with your wattage numbers/ Each home and location is different. Why not try the LG and get some numbers before you complicate your life.

bill von novak

Dave Angelini said:

Finally an energy saving window unit built that requires little skill to install. Gamechanger from LG

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

Excellent.  

I suspect that there will quickly be a "hack" to allow setting A/C power to match excess solar generation, so that for zero-export and off-grid installations you can ensure that you are running entirely off solar (rather than grid or battery.)

Dave Angelini

IFTTT already does similar with wifi called a smart switch. The LG window is not as good on energy as the top splits and does not have the heat function yet.

I think others will start doing this. Their pricing indicates to me it is not much more for a consumer than the low Fi window units that abound.

 For Offgrid it would be an excellent spare to get you through until you are brave enough to go back to the big city

Photowhit

I hope the technology is easily scalable, I'd like to see a 20-25% increase in efficiency for 5-1200 btu units! 

Maybe next season.

Nesto

Bill & Dave, thanks for the reply,and, after posting I basically came to the same conclusion; try it out first and measure use. As to a solar set up, it would be off grid and my thinking is to just use the panels to power the a/c from about 10-5 which would save me a lot of electricity keeping me in that 2nd tier of SCE rate. I went into that 3rd tier June-Sept and that rate really spiked my bill. I really don't see batteries running these after  panels stop producing enough watts. I would probably have a small battery back up just to store any excess power the a/c didn't use.

What do you think? 1200 watts of panels to run the a/c during day only? 

House has blown insulation and is well vented and in good shape. walls also fully insulated. I'm here in the Los Angeles area. My hvac works great it's just the damn cost in the summer. If i could get 3 of these units to cool the areas we actually use in the house; bedroom/tv room and kitchen, (1100+/- sqft.) and I could run 6-7 hours on solar this would really save on my bill. I figure about $2,300-2,500 cost per unit (a/c, panels,inverter/cc-i have wiring/channel to mount etc).  3 units, total cost $7,500. if i save $400 a month for 3.5 months each summer the payback is about 6 years. The cost vs. payback is worth it to me. I can't see spending any more than this to get full solar for my house. I;m pretty stingy on using power. My bill w/o ac is about $120 per month and that's running my variable speed pool pump 4 hrs a day; frig/wine frig inside, outdoor frig, timers/motion detectors on all lighting.  (yeah, i know I could close vents to rooms that we don't use but I have read this is not good for a forced air system/and mine works great).

As to the lg-lw1517ivsm ac, i just took a look at one and i thought i read a thread somewhere that these lg's were a/c and heat. Am I wrong about this? the lg is a/c only? thanks for the reply's, oh, and if the lg is a/c and heat, what's the model number? 12k or 14k btu. 

Nesto

Not sure if this belongs here, but Dave had a post of running a  split air system. "My second unit is an LG split and it is very similar to all of the good things we liked about Sanyo. Sips power at 28 SEER". Dave, how would you set something like this up to run off grid solar for the 10-5 time period i am trying to do?

Dave Angelini

Nesto, I try and help here with general info. 

Specific info from my electronic field testing and close to 30 years of experience with 200+ offgrid homes is my business.

Estragon

If you want to do it "off-grid", you'd need a battery bank big enough to power a unit in the early morning / late afternoon when solar power provides lower current and/or when a cloud passes, and an array big enough to both supply the load and charge batteries during peak solar hours (+/- 11am-2pm).  Almost everywhere, grid will end up being cheaper.

If I was doing this, I'd look at using an inverter that can use solar to offset/supplement grid (as opposed to full grid-tied with sell-back.

Photowhit

Looks like they making these in other sizes, They had a dual inverter compressor in a 14000 and 18000 btu last year.

I can't find it on their website, but looks like a 9500 btu got it's Energy Star rating last week. No idea about the price or availability yet, but it has a CEER of 13.8, Most/All other window units in this size are <12. Not as good as the larger 14000 with a CEER of 14.7, but I needed a smaller unit for my 400-450 square foot main room.

It's a LG - LW1019IVSM according to Energy Star;

https://www.energystar.gov/productfinder/product/certified-room-air-conditioners/details-plus/2334753#PriceAndLocation

Photowhit

BTW- the energy star ratings on the 14000 btu unit were pretty impressive! When compared to other units which used between $115 and $182 worth of electric it used $68!

Dave Angelini

That is a nice EER also. I saw the 14kbtu at Lowes last week. One third the price of a similar split.

wankel7

I have done a lot of internet trolling and I can't find a single person who has purchased the 14,000 unit and actually tested it's power consumption. Nor can I find any specs on what the BTU range is. Most mini splits publish that spec.

The 9500 btu one will be interesting....

Dave Angelini

I saw them at Lowes last week. Most offgrid users would be better off with a mini-split for low energy use.

wankel7

Dave Angelini said:

I saw them at Lowes last week. Most offgrid users would be better off with a mini-split for low energy use.

I think this type of unit will have it's appeal with travel trailer owners and vans. More so with vans since a mini split is pretty difficult to do.

Photowhit

@wankel7 "I think this type of unit will have it's appeal with travel trailer owners and vans. More so with vans since a mini split is pretty difficult to do. "

The new and smallest is 9500btu large enough to for a 450 square foot room!

@Dave Angelini "I saw them at Lowes last week. Most offgrid users would be better off with a mini-split for low energy use."

If they have 240v available. I haven't seen any real high SEER ratings for mini splits that were not 240 volts. I suspect these would be pretty close to the 120 mini splits. LG eluded to perhaps it would be time to use comparable rating systems.

wankel7

Photowhit said:

@wankel7 "I think this type of unit will have it's appeal with travel trailer owners and vans. More so with vans since a mini split is pretty difficult to do. "

The new and smallest is 9500btu large enough to for a 450 square foot room!

Right but it is variable speed.....oversizing is less of an issue on variable speed.....it will quickly reach the set point an then roll back.

Dave Angelini

Agree with both you guy's. They are a step in the right direction and LG is to be applauded.

wankel7

Looks like LG is putting variable speed in all the things....

https://www.lg.com/us/air-conditioners/lg-LP1419IVSM-portable-air-conditioner

Dave Angelini

Are you going to get one? Everyone of the portables I have seen were pretty unremarkable to me. If the 1419IVSM is decent, it should work really well for the RV crowd or anyone needing portability. 

Mike_in_PA

I picked up two of these 14 kbtu LG dual Inverters 6 weeks ago in anticipation of a hot summer.  Installed one last night into master bed/bath/closet area, ~ 700 sq ft and lots of windows. The rooms were hot and humid.

After running all night,  the Killawatt shows 250 watts usage.  I didn't plug the Killawatt in until this morning, so can't say what it used overnight.  Temp is set to 67, fan on lowest speed.  The rooms are very dry.  This is better than the LG 9 kbtu mini split I put in a client's house.  And when the compressor is throttling up or down, it sounds just like the out door unit on the mini split sounds when throttling up or down. 

I'll leave the unit running for the next 24 hours and provide usage numbers here. 

Long term reader, first comment.  

cow_rancher

Mike_in_PA said: Temp is set to 67, fan on lowest speed.  The rooms are very dry.  

And why would you have the temp set at 67?

Rancher

Mike_in_PA

Yesterday, from 6 am to 10 pm (16 hrs) The LW1517IVSM used 11.5 kwh. 720 watts (average) This was with a door open from Mbr to stairs, letting cold dry air flow downstairs and keeping the LR drier and more comfortable.  Temp outside mid 80's.

Yesterday to today, 10 pm to 6 am (8 hours) used 4.75 kwh, so 590 watts (average).  Door to downstairs closed. Fan is on low.

I realize this is not a complete description of the operating conditions for the AC.  Just wanted to get some watt numbers out there for people like me who need a ballpark idea of how something is going to perform.  The AC rated amps are 12.0; I never saw the unit go above 900 watts, so 7.2 amps (utility line voltage is 124/248)

With fan on lowest speed, it is still putting out a river of cold dry air, and it's very quiet, considering the condenser fan and compressor are right there in the box.

why 67 deg F?  No reason, I have almost always managed without AC at home and at work, so I really have no idea what a good sleeping temp is supposed to be. Plus it was hot and 100% humidity two days ago when I put it in.  Cold felt good.  Should probably be set mid 70s.

Someone could do some proper testing on this thing.  

Dave Angelini

I think the question of why 67 is a good one and is part of "proper testing"
People are told by the government to set at 78F. There is some logic to it but that is a bit high for me.

A realistic test for an offgrid home is probably around 75 F at night and anything you want when the solar is on. The best test would be just 75F for 24 hours, and then subtract day time KWH. The split here can run about 3 KWH at night but that is with a pretty warm night, or lately a smokey night

mcgivor

The temperature setpoint is irrelevant in itself, outdoor/indoor  temperature along with insulation value have to be factored into the equation, modern air conditioning units use outdoor and indoor temperature sensors to regulate the cooling output to prevent hunting. Non inverter type cannot vary the compressor speed making them inherently less efficient due to their inability to modulate, it's either 100% or 0% making for a less conformable environment. 

The energy guide figures are probably the most accurate for comparison purposes between units because it's a level playing field, but not necessarily accurate for personal use expectations which could be > or < quoted Everyone has a personal comfort temperature for sleeping, for example 27°C or 80.6 °F works for me, others may think this is a hot summer day type temperature.

With my split system, the overnight the energy useage can vary between 2.5Kwh with outdoor 35°C, to less than 1Kwh when 28°C or less, ceiling insulation is R21, walls are lightweight thermo cement with ceramic paint, no direct sunlight during the day, attic temperature >50°C in direct sunlight, irrelevant during the night.