inverter AC's

Gregaba

I could not find an off topic thread so though I would ask here.

I am going to have to replace one of my 98 year old mother's window ac unit before summer.

She doesn't have solar but I stumbled across an inverter AC and wondered if any one has used these yet?

They claim a drop in electric use of %40 to %60 over standard unit's.

If that is so I am considering one for my shop.

12,000 btu for $475.00.

Greg

Dave Angelini

On the forum here since 2008. In each make and model there are more efficient models and you will pay more than $475 for the really efficient high SEER models !

https://forum.solar-electric.com/discussion/23007/mini-split-update-for-offgrid

Gregaba

Dave

Thanks for the link.

Greg

JRHill

While the topic of AC is fresh....

We don't have AC. We don't need much even at its worst. If its going to be 100F+ outside and if we close the windows by 9am its not bad and rarely gets above 85F inside. But there are those weather patterns that even the night time temp doesn't drop enough to cool the inside down. Then it gets gruesome. OTOH, if you step out for a few minutes and come back in you'd think you walked into a fridge.

I have kicked around one of those 120v units with the tubes that sucks in outside air and blows it back out. I'm not interested in the one tube units. We're like a Ruskies with vodka in the summer with solar so it would be no problem during the day. Has anyone anything good to say about these units? I looked last summer but they were crazy expensive and sold out at peak summer. Now would be the time to start shopping.

Our power use is very low, esp mid day so the 3600 watt inverter wouldn't be challenged in the least. The other thing is our windows are all horizontal sliders so a standard AC doesn't fit. Any input?

Ralph Day

JR, I've seen ac units made for those type of windows.  They're tall and narrow instead of wide and short.  But a heat pump works great.  I have a 12.000btu unit.  It only uses 300 to 600 watts cooling, but over 1000 watts heating.  Must be the delta T that makes for more work.  AC you're just trying to change temp by a few degrees whereas heating the delta T is much greater.

Gregaba

I am still interested in these unit's. We have to have ac here as we have had up to 52 day's of 100+ degree day's before. Normally we only get 10 to 12 day's but at midnight it can get up to 100 degree's.

When I was a kid living in the country we used to take our bed's outside so we could get at least a little cooling at night. Live in town now and don't think that would work.

If I can find one that just use's 300 to 600 watt's I would seriously look into it.

Greg

Dave Angelini

Easy to find ! They are variable speed compressors! They work on the differential of programmed temp to actual room temp. If you keep the differential low and use a 9,000 btu or so minisplit there will be roughly 300 watts and 600 watt modes that you can program. As the room cools you have to change the differential as the thermostat will lower power to near zero watts. You can also get into modes where it will be 1 and 1.5Kw if you program the temp differential up.

The big warning here is to use the best model in the size (9000btu)  from quality companies like Fujitsu, Panasonic, Mitsubishi, and so on. You want near 30 SEER.

About a quarter of my clients use a split just to keep the wildfire smoke out. There is alot more to this strategy that I keep personalized for a client. No one likes smoke in the house! Used the first Split to test offgrid for Sanyo in 2007.  GAMECHANGER and it heats !

JRHill

Thanks for the info Dave, Greg & Ralph.. Our place is a 12 YO 1350sq' log in the chalet style. Pretty tight w/6" of urethane above the ceiling. An air tight wood stove in the main room covers us even in single digit weather. The problem is PNW cloud cover requires 2.5 months of battery charging by generator. Running a generator to charge batteries to keep a heat pump going is not going to fly with the DW.

I think the mini split would be out but could be a nice value add in the long term. What my interest is is for the summer and AC. And a casement window AC should take the edge off the inside temp and at the time of the year when we can not begin to use all the power we COULD create.

Dave Angelini said:

 You want near 30 SEER.

I'll have to keep looking and researching. I see plenty of 20 SEER units but nothing close to 30. Because of where we live its going to have to be a self install, or my with a laborer/helper.

We'll see where this goes.

Dave Angelini

Look at the best/most expensive models in the BTU range. Look at Fujitsu and LG. They are at 30 SEER.
You will have to give up warranty if you self-install. We do this all of the time for Offgrid.
I use to fly out and do this as I still had my Cali license for that. I Liked Hawaii !

For you, I would just buy a good variable speed inverter window unit. Cut a hole in the wall and you are set. Buy it on your Home Depot charge card and you have 1 year return to Home Depot. Search the forum here. You did have a nasty hot summer last year and might do the same again. Too bad they do not make a window unit that variable speed heats....   Good Luck !

JRHill

Dave Angelini said:

Cut a hole in the wall

You don't just cut a hole in the log wall.

Ralph Day

JR, it's called chainsaw carpentry for a reason 

JRHill

This is the 2nd log home I've built. In both cases the companies hired to stack the logs and finish the dry in were absolute artisans with their chainsaws.

Dave Angelini

Get an artisan to cut the hole