Mini Split update for Offgrid

XRinger · May 2015

You can actually ignore the manual and mount a wall unit down near the floor. (Easier to install).
It's easy to look down into the top of air-input vent and see if the filter needs cleaning.

The disadvantage is hot air up near the ceiling isn't pulled into the unit. Since cold air stays near the floor, the input air is pretty cool already.
So, if you stand on a chair, the air up at the ceiling is going to be pretty warm. Combat this, by sitting in a LazyBoy chair..

During the heating season, it's sucking in the cooler air near the floor, which works out very well.

The other disadvantage is the eyesore effect. It's 22% worse than a high wall mount. But, my wife gave up caring how these things 'look', after using one for a while..
Inverter ASHPs Rock!

http://ecorenovator.org/forum/geothermal-heat-pumps/1815-2-sanyo-24khs72-ac-hp-install-project-oct-2011-a.html

Dave Angelini · May 2015

Mounting the compressor in the kitchen?
Hey Rich would you have any advice on getting a spare remote for the Sanyo units? A learning remote or something?

XRinger · May 2015

NO! Not in the kitchen.. It's right outside the den.. http://ecorenovator.org/forum/geothermal-heat-pumps/1815-2-sanyo-24khs72-ac-hp-install-project-oct-2011-a.html

I've used the number on my remote to search on-line, and I've seen them for sale at a few dealers and on Ebay. Mostly not cheap.
Saw them for $20 once a while back. Wife wouldn't let me order one.. "We already have two, and you would just lose a new one"....

Not sure how well a learning remote would work.. All the ones I've seen are for entertainment devices..

GaryO · May 2015

Group:

I was directed to this thread by another user. It seems like some of you may have some good advice for my new installation.

I am finishing up a cottage on an island (1200 SQFT on 2 stories). I have NO utility service, so all power will have to be derived from solar and a generator (off grid).

My daily loading has been calculated to approximately 3000 Wh per day, but in addition to that, I also wish to use a mini-split HVAC system to cool the building.

I plan to use a 12,000 BTU (29 SEER) unit and a 9,000 BTU (33 SEER) unit to accomplish this. They use a maximum of 800W and 500W, respectively.

This drives my relatively meager power requirements to a whole new level. My original plan was to simply turn on the generator whenever either unit called for cooling (which would allow the inverter to both charge my batteries and handle the potential 1300W of demand). The generator would turn itself off once both units satisfied the cooling setpoint.

I'm curious how the rest of you have handled this problem? Is there a more elegant or efficient method than what I described above?

Thanks in advance!

Dave Angelini · May 2015

What Makes/models are you using? How did you ever calculate 800 and 500 watts? If you read the first post in this thread and some of the later ones you may get a better idea of this strategy.

GaryO · May 2015

Dave -

I've read throught his whole thread. These are the Fujitsu 9RLS3 and 12RLS3 units. The wattage was pulled from their spec sheets.

From my research, these are the highest efficiency units available.

Specs can be found here which call out the cooling input wattage: http://www.fujitsugeneral.com/wallmountedRLS3_down.htm

Your question about model makes me wonder why so many here seem to have landed on the Mitsubishi units. I know they sell a lot of mini-splits, but I would expect this 33 SEER efficiency to be really attractive to anyone running off-grid.

MarkC · May 2015

FYI;
I've used an Amana PTC style AC/heat pump/htr strip unit for several years (11,700 btu/hr rating). Recently tested the VA consumption using my (Priups generator) set up that continuously logs VA usage (APC SURT 6000 data logging). The results varied between 840 and 940 VA continuous including all losses in system. The UPS inverter is located ~150 feet from the AC unit, with multiple breakers, inverter losses, etc, so the actual VA usage of the Amana could be different in another system. I don't have a watt meter, but I assume the actual wattage is even lower with this "reactive" type inverter. This unit is rated at 230 volts, but I've set the UPS output voltages at ~ 240 volts (unit does not carry a neutral even though the system does produce conventional split phase 240 volt power through the SURT003).

I was quite surprised at the low amperage readings as the "nameplate" amps are 4.8 - 5.2 (1100 - 1200 VA at 230 v). It was cool that day which could explain some of this.

The advantage of these units are simplicity in installation, the big disadvantage is they must be installed on an outside wall.

Dave Angelini · May 2015

GaryO wrote: »

Dave -

I've read throught his whole thread. These are the Fujitsu 9RLS3 and 12RLS3 units. The wattage was pulled from their spec sheets.

From my research, these are the highest efficiency units available.

Specs can be found here which call out the cooling input wattage: http://www.fujitsugeneral.com/wallmountedRLS3_down.htm

Your question about model makes me wonder why so many here seem to have landed on the Mitsubishi units. I know they sell a lot of mini-splits, but I would expect this 33 SEER efficiency to be really attractive to anyone running off-grid.

Gary-

I would not be concerned with the brand as long as it is a good one. Mitsu runs quite a few adds on TV and that is what sells to the masses. They are great units also which helps. Fujitsu was one of the few that was really good with do-it yourself. Many offgrid locations are so remote that it really is the only way.

The specs on the 1 ton are confusing. There is a rating for the outdoor unit at 800 watts rated cooling level. There is another rating in the brochure I looked at that the said .99 KW at max cooling.
I tend to believe that your 800 watt spec is averaging. and the real consumption could be .99KW. I am comparing that to my direct experience with a 1 ton LG that was 25 SEER.

These are still very good numbers but you must account for the power. If you have a structure that is not well insulated you will really have to babysit power use on your offgrid home unless you have 3 or 4 KW of solar. On an island in the tropics the afternoon clouds can really cause the need for a larger battery bank also. Is that where you are?

GaryO · June 2015

Dave Angelini wrote: »

On an island in the tropics the afternoon clouds can really cause the need for a larger battery bank also. Is that where you are?

Oh, no... I'm on an Island in Midwest Ohio! However, the cottage is new construction and will be well insulated.

I have also seen conflicting specifications, however you will also notice the max current rating at 230VAC is consistent with the lower wattage. Also, you can back into the wattage since SEER rating is the BTU per watt.

At 33 SEER, this 9RLS3 unit seems like the hot ticket for off-grid to me. I just need to figure out the best way to allow my generator to automatically supplement it when it calls for cooling. I would need a much larger solar and battery system to cover these loads required by an HVAC system that I think using the generator for this is the right answer.

Dave Angelini · June 2015

Yes I agree the models are really as good as it gets right now and I changed to these on a home I am doing later this summer. Thanks!

I would really hate to have to use a generator with solar so cheap and reliable. If I were you I would just use one Split and wing it with panels laying on the ground or whatever you have to do.
You really need an east and west array.
Get some help! Being hot and sticky is nasty in 2015. Good Luck

Anawa · June 2015

Dave, finally got around to hooking up the Mitsubishi units on WiFi. Here is a follow-up and an overview.

First, the set-up and installation is seamless, probably would take 30 minutes for 2 units if installed during unit installation.

The handheld units are unique to each mini-split, thus the one hand held unit for all is not an option. However, the programming options for the hand held are staggering .... meaning way more than the average homeowner would use. You can program in just about condition imaginable.

The web app is simple and controls up to 4 thermostats that are clearly identified on the app. You can monitor indoor temperature as registered on the hand held remote, turn on/off the unit, set-up email alerts for high/low indoor temps, and other email alerts regarding WiFi interruption.

I have about $500 invested in this technology and can see the value in this by being able to remotely monitor and implement the limited user controls on my off-grid home. Of course, I'm not present at this location full-time and that's where the value is for me.

Paul

Dave Angelini · June 2015

Thanks Paul for the update. It does sound like a match for your not being there all the time.

The one condition I am always looking to automate is a way to use the conditioning of space in a home that is throttled by available power.
This would take data from charge controllers, inverter, and the mini split to implement. The other way to do this is a setpoint from the CC aux and a solenoid. I have done this and it is too clunky for most people. I guess the third way is too just have much more solar than a human has a need for to cover cloud conditions.

Dave Angelini · June 2015

Sanyo replacement remote!

Hey Rich or anyone who needs a remote for a Sanyo or probably alot of different equipment that is not being made anymore.

I just typed the model of the remote in and did a google search. The first line was Amazon with free shipping $18
It shipped by China Post air mail to USPS from HC Electronic technology CO LTD in beautiful downtown Guangdong.
It arrived yesterday 3 days after I ordered it on amazon. It works and here is the model number I used. The company was very concerned that I was happy and gave an e-mail for a pretty Asian lady named Wendy pictured shaking hands with this man.

http://www.amazon.com/Replacement-RCS-4HVPIS4U-24KS72-KS2472-INVERTER-Conditioner/dp/B00UV3TLRO

XRinger · June 2015

Thanks for the tip Dave! I see they are also on Ebay now. A little cheaper there, but 3 days with Amazon? That sounds amazing from China..
I'll have to get one. It will be good insurance that my two remotes never get dropped..

Cheers,
Rich

Lurker · June 2015

How about a dc powered model

http://www.hotspotenergy.com/DC-air-conditioner/

Dave Angelini · June 2015

The hotspot has come up over the years but they did not have the energy saving compared to the best AC powered inverter splits or models that were readily available to buy. (nobody bought one and reviewed it)

XRinger · June 2015

Dave Angelini wrote: »

Sanyo replacement remote!

Hey Rich or anyone who needs a remote for a Sanyo or probably alot of different equipment that is not being made anymore.

I just typed the model of the remote in and did a google search. The first line was Amazon with free shipping $18
It shipped by China Post air mail to USPS from HC Electronic technology CO LTD in beautiful downtown Guangdong.
It arrived yesterday 3 days after I ordered it on amazon. It works and here is the model number I used. The company was very concerned that I was happy and gave an e-mail for a pretty Asian lady named Wendy pictured shaking hands with this man.

http://www.amazon.com/Replacement-RCS-4HVPIS4U-24KS72-KS2472-INVERTER-Conditioner/dp/B00UV3TLRO

I wanted the RCS-4HVPIS4U, (as shown in your Amazon link) but the vendor sent me a RCS-4HPN4E-T.
It doesn't work at all.. I saw the Sanyo was going nuts, so I pressed the off-button and the door closes,
but the fan motor stayed on and the LED didn't go off!
I emailed Wendy and I'm hoping for the best.. Attachment not found.

Dave Angelini · June 2015

I had the same part numbers old and new and they work fine BTW. You must have got a bad new unit. --Dave

XRinger · June 2015

It's missing a button on the inside panel (Quite). And the ION button up top is relabeled Quite..

Dave Angelini · June 2015

Say hi to Wendy!

XRinger · July 2015

Dave Angelini wrote: »

Say hi to Wendy!

No luck with Wendy & company. Standard form letter replies. Then, "it should work". I'm getting nowhere.
I guess they don't mind getting a bad review on Amazon..

So Dave, do you need a spare spare?

Cheers,
Rich

Dave Angelini · July 2015

Sorry about Wendy. She seem so sincere and now she has broken both our hearts...

What I need is someone who can write MODBUS software to control a MODBUS thermostat and take some basic data from MODBUS on an inverter and run a simple algorithm.

How has the Summer been? Watering the garden with condensed water from the split?

XRinger · July 2015

Dave Angelini wrote: »

Sorry about Wendy. She seem so sincere and now she has broken both our hearts...

What I need is someone who can write MODBUS software to control a MODBUS thermostat and take some basic data from MODBUS on an inverter and run a simple algorithm.

How has the Summer been? Watering the garden with condensed water from the split?

Never heard of MODBUS.. But it seems to be some kind of strange machine code.. Not even assembly code!

Nope, we are still waiting for the city to activate our new water meters.. So, we are using H2O freely for now..
Right now, one of my best PV panels seems to be dying..

Got some micro cracks and water got in.. The temperature around the damage is over 100deg F hotter than the other segments in the same panel..
It's like 230 F right now.. And I've covered it with some foil, to keep the sun off it.. But I guess it's the pass-thru current.. Hope it doesn't burn up the whole panel..

http://ecorenovator.org/forum/solar-power/1284-cs6p-200-canadian-solar-pv-xantrex-c40-project-6.html#post45979

BB. · July 2015

Disconnect it from your array (you may need to re-wire some other panels depending on the configuration)...

You are probably running a risk of fire with that panel. It is not helping now.

-Bill

XRinger · July 2015

The sun has been a bit dim today, but the power was still pretty good. Over 6A into the 13 ohm hotwater heater element.
400-500 watts is about 1500 BTUh going into my tank..

I put a blue tarp over the array and waited for the clouds to roll in.. (We almost always get clouds these days).
Once the output dropped down to 1A, I opened the 20A toggle switch. (Hope it didn't fry).
Then put in a jumper to bypass the bad panel.. 3 panels isn't going to work very well.. Not a match to 13 ohms..

What to do with the bad panel? Just try to find a new CS6P-200 Canadian Solar?

Dave Angelini · July 2015

Junk-it ! That model is now up to over 300 watts now. What was the MPV and VOC on it? Good that you disconnected it, you get enough lightning there don't you?

We had some last night in the high country but hurricane Delores is coming up our coast and there are already feeder bands today. They mostly always go west and miss us, mostly....

XRinger · July 2015

I see them on-line, but you can't just buy one panel... It's two minimum.. For a good price, 48 units..

Attachment not found.

Dave Angelini · July 2015

That will be hard to match, how old? Most all Canadian Solar now are all around 36V vmp and 45 voc and at over 300 watts now you would be limiting current to your old panels.
Solar is pretty inexpensive now and I think it would be good for the economy for you to buy a new string......

XRinger · July 2015

Seems like getting the most hotwater out of the 3 remaining panels shouldn't be too hard.. (With good sun).
29v x 3 =87v / 13ohm = 6.7a 583 watts.. Almost 2,000 BTUh..

If it's not enough, I can reconnect the old 500W tracking array (to the second 13 ohm element) to more than make up for the loss..
I guess we can get along without that old broken panel..

Edit:
It's really hot today (which makes the panels perform poorly), and we are seeing 5.9a into the 13 ohm heater element.. That's 452.5 watts! Or 1544 BTUh..
That's about 75% of what it should be on a nice cold sunny day..

Dave Angelini · August 2015

Hey Rich, How did you end up with the remote unit from Wendy on amazon?

Have you ever hooked up an external wired thermostat to any of your units? Is it just a matter of removing the thermistor on the indoor unit and wiring a standard 24V wired thermostat?
I have the manual for the kit (STK-RCS-7TWSUA ) Sanyo use to sell and it looks like a proprietary connector. Any thoughts?

Mini Split update for Offgrid

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