Finally an energy saving window unit built ! Wow

Wheelman55

MrM1 said:

Un related... But our 2 ton mini split 21 seer cooling our 40x30 shop settles in at 2.8 amps 

MrM1...are you running this 2 ton mini split off of your 2.6kw array?

MrM1

Wheelman55 said:

MrM1...are you running this 2 ton mini split off of your 2.6kw array?

No This is in a Grid System.  It was just interesting to see the low numbers of a mini split.  I am also NOT running the LG Inverter Compressor 9500 BTU unit off my Solar Array.  Posting it here because that is what this thread is about.   I just bought the LG for my office.

The LG has now been running for 45 minutes in a 450 sq ft room,  and the temp is dropping.  Cant say how much,  BUT even set to 60°F Amp draw has gone down to 8.25.  So the Compressor is not working as hard.

Raj174

@MrM1
That's awesome, let us know what the amp draw is when the room reaches a comfortable temp and adjusted the thermostat to match.

MrM1

Now the LG 9500 BTU "Thinks" the room is 75°F (according to the unit via the wifi app).  With the unit set to 74 it seems to more or less go into a maintenance mode and has settled into about 3.1 amps and sometimes going back to 7.3 amps to maintain the room.  Air blowing out of the unit to the skin is still cold even at 3.1 amps.  Outside temp is 84°F. 

MrM1

LG 9500 btu has been running since about 4:30pm, about 4 hrs. Room had no ac prior to install and the window was open while installing. Room reach 80+. 

After 4 hours now, out side temp is still about 80.  Room is 450 Sq ft.

The LG says the room is.... 



About an hour and a half ago I place a temp sensor in the room out of the path of the blower 10 ft from the LG. It's still dropping but says...

Dave Angelini

So that is about what I saw at my neighbors full on. Why not measure with a 75F room set on 75F and use a power meter over 2 or 3 hours in auto. Much more useful data for someone.

The sound level on all of these are amazing. In and out!

MrM1

Thanks I will do that.  I did get a reading at 75F set to 75F at it was still cooling but running at 3.12amps.  I'll go over now and connect a Kill-o-watt meter and run it all day set at 75 with the room at 75.  Outside temps will be upwards of 90 today in FL.  I'll look at the meter tonight and post back in Watt hours used. 

MrM1

Kill-A-Watt test of the LG 9500 BTU Inverter compressor unit

Conditions:

• 12pm Saturday
• Outside was 89°F
• Outside humidity was around 75%
  
• Inside at start was 75°F
• Room Size is 450 sq ft

Attempted to keep the room at 75°F for the entire test time.  LG had to be set to at 73°F for my Ambient Weather WiFi temp sensor to read 75°F. This sensor was place 10 ft away from the LG window unit.   The LG temp sensor read 74°F.

Test ran for 19.27 hours (12pm Sat - to about 7am Sun)

Kilowatt hours  used 6.61KWh

jonr

That's an average of 343 watts.  But nobody can count on this value because their Btu load will vary.

Dave Angelini

Thanks MrM1 ! 

 The offgrid strategy would be to get the room as cold as you like during the day and back off the set-point at night after sundown. The size here is easily useable in a 1800 square foot house. The cooling is dependant on the load and with some kind of tracked array we run dawn to dusk off the sun and reduce set-point at night. Plenty of people can count on this load BTW, Plenty! I often see 300 watts at night including a 150 watt refrigerator cycling. So do many of my clients so your numbers are not surprising, to me! 

A robust enough system can do it all offgrid!  It just can't do it all at once   Looks like Florida luck is holding out!

MrM1

No doubt on the storm turns 

Cryptogenic

Did your installation go well?

MrM1

Yes went in very easy 

wooffi

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

I have that one, great unit and quiet too. The funny thing when you look to India they already have most appliances with dual inverters, washers, fridge/freezers and even microwaves. Of corse the US as always with alternative technology lacks way behind.

Dave Angelini

Go ahead and write how the US lacks. You are free here to say that. Many places in the world there is a limit on what you can say.

Personally, I think the technology in India, probably came from an engineer educated in the west. There are great products from many places in the world. There also are other reasons that India has to do what it does energy wise compared to the US.

I bought a Panasonic inverter microwave at costco 9 years ago. It did not get great reviews (rusting) but it is ok.

Marc Kurth

Dave Angelini said:

Most people I know don't have or abandon the ducting in a central air system. It wastes energy, is hard to clean and not needed except in very, very large offgrid homes.

Dave, I'm not offgrid but my duct system is all contained completely within the conditioned space. With oversized low velocity duct sizing, I can effectively use the zoning system to allow rooms to be shut off, sending its intended airflow to other rooms for increased performance. Starting over, I would likely use mini splits. (I carried a C-20 HVAC license in CA in the 80's and 90's)

Dave Angelini

Well that is the way to run ducting for sure. I have not seen one like yours in over 200 homes now. Very cool, pun intended.

Marc Kurth

My fan coil hangs horizontally in the laundry room downstairs with the duct work run around the perimeter of my 32' x 40' two story footprint . So downstairs has high sidewall registers with furred in ducts, but upstairs has floor grilles. Some people are afraid of floor registers for cold air, but a little ceiling fan action solves that problem, like it does with heating being supplied from ceiling registers.

I am big on recommending what you have been saying in this thread. What I have is not cost effective today - it was done by the previous owner when I wore a younger man's clothes in the late 70's

The guy who built this place was clever. The chimney has four separate flues for the two fireplaces - and ducttwork buried in the brickwork for convection flow. We are able to heat the whole place with wood down to 20F with the central heating fan only, but that description is for another time.

Estragon

My 1960's era city bungalow is much the same, with both heating and cooling delivered via conditioned space ducting at grade. 

Unfortunately, they weren't so smart with brickwork, and wood heat probably hurts more than it helps   

ce_smith

New here on this forum. Wow! What a wealth of information you guys have here!. I will start researching solar for a boat that I am searching to purchase. In relation to this thread, some of you might want to look at Bosch's new DC Inverter ducted condenser unit for those who need a ducted system. Bosh is now on the 2nd revision of the unit. It works with existing blower units and I have read lots of reviews from HVAC techs who have installed them in their own homes. Starts out around 3 amps and ramps up as needed. It does not need a communicating thermostat to work. It controls the modulation from a sensor of the suction pressure of the condenser unit. I have a 26 year old Waterfurnace geothermal unit that is on its last leg and no geothermal HVAC companies in my area, so looking hard at the Bosch Inverter heat pump as a replacement. The seer rating is not as high as mini splits, but for a lot of people, this is great to have an DC inverter ducted split system. It is also priced right. Only two size units offered since all that you do to set capacity is change a dip switch between 2 and 3 tons or 4 and 5 tons. Also can set coil temp at 37 or 47 degrees by dip switch. 

Dave Angelini

https://www.bosch-thermotechnology.us/us/en/ocs/residential/inverter-ducted-split-system-ids--1098928-p/

This one?  It might be good for someone with a 26 year old system. But as you see it is only 18 SEER and unless you have ducts in really good shape and are not lossy, I would consider a couple split units. I have very successfully done this in old homes more times than you would think. The biggest mistake to avoid is using a single inverter compressor and multiple air handlers. They just do not have the SEER of the individual units. The 2nd mistake is too much BTU. This again is because the larger units never have the SEER of the smaller ones. This could change but I have not seen this and look pretty often for my offgrid folks. Most of the top splits are over 30 SEER BTW. The heating is almost 4 times as efficient as a resistance heater. Some of what I am saying may not apply if you have the grid and energy is not expensive.

And the loss is about 30% on a newly installed duct system, maybe a tad less if the ducting is in conditioned space like Marc's above.

For less than $500 you could test the 9.5kbtu here from LG and it could be a gamechanger for someone like you. No heating yet on this unit though.

Here is a link to where this started for offgrid, I think...
https://forum.solar-electric.com/discussion/23007/mini-split-update-for-offgrid/p1

ce_smith

All my duct work is in conditioned  space. Some of us have houses that installing mini splits throughout the whole house is not possible and very costly. My home for being 25 years old is well insulated with cellulose in the walls, thermobreak windows and metal roof with Styrofoam between trusses. Yes, higher seer is better, but if the unit cools the house down and then modulates down to 15% capacity, that is efficient. You can also zone with the Bosch. 

Dave Angelini

Great !  As I said this may not apply to you.

bryhan67

I just ordered the 14,000 btu for my off grid beach house. Daytime I have surplus with 10,000 watts of solar panles but over night have to run all power on batteries. Whats the lowest amps you get it to draw regardless of temps? Example its 85deg inside but you set it on low or energy mode can you force it to stick to 3 or 5 amps? What I liked about the little 6000 btu is i know the max power it could take aout of my better bank. Some nights I was cool others was just to hot. Would be nice to lock in the max power it could pull while I sleep. I know I could raise the thermostat but it would be a moving target every night.

Dave Angelini

I would have used the smaller version (above is a link) of this LG. Just too close to the edge for overnight use on batteries.

Marc Kurth

I will throw in another comment on the wisdom of slight under-sizing: Humidity control.

Consider that a large cooling system immediately cools the space - so it does not run long enough to extract much moisture. A smaller unit will run longer, allowing the coil to do more latent extraction.

This is less of an issue in dry climates of course, but it can be a real problem in many homes even in arid climates.

Marc

Dave Angelini

Definitely keep the bugger running. I have a client in Florida who has never turned it off......

Even better with a reverse cycle pump as you can heat with it. Alot of that would I use to cut for heat is now being sold to other people.

wankel7

Has anyone tried the other sizes from LG?

The 9500btu has a ceer of 13.6. 8k is 15.5 and the 10k is 15.0. 

Trying to figure which one is best for our van. 

Photowhit

Might look into a 8000btu Media, very efficient/quiet unit.

There are some threads here about it, some installed unit reports, in homes none in vans to my recollection.

Amazon.com: Midea 8,000 BTU U-Shaped Smart Inverter Window Air Conditioner–Cools up to 350 Sq. Ft., Ultra Quiet with Open Window Flexibility, Works with Alexa/Google Assistant, 35% Energy Savings, Remote Control : Home & Kitchen

Dave Angelini

Fairly quiet inside but nothing like a split outside if it is working hard. Not bad when it is cruising and the temp differential is low.