Mitsubishi mini splits off-grid?

[RV10flyer]

If the meth heads that are HVAC (at least in my area) can figure it out, any person with decent mechanical aptitude can get it done. Granted mechanical aptitude is a dying trait.

Why do you think Mechanical Aptitude is a dying trait? Maybe because too many people look down on those of us in career fields with two years of tech school. Why would anyone want to be a shop/school teacher? So they can make less money and get berated by their 4 yr degree holding peers? The greedy rich, those in positions of power, many of those with 4 yr degrees, have succeeded in outsourcing the United States for higher profits that have went in their pockets for the last 40 years. Very little mechanical aptitude is needed anymore as the junk is made unrepairable or uneconomical to repair. Gotta keep GDP up and the lower class down by selling new junk all the time. It’s no wonder that it’s a dying trait. About the same as Integrity and Accountability for the last 416 years.

 

[SilverbackMP]

Why do you think Mechanical Aptitude is a dying trait? Maybe because too many people look down on those of us in career fields with two years of tech school. Why would anyone want to be a shop/school teacher? So they can make less money and get berated by their 4 yr degree holding peers? The greedy rich, those in positions of power, many of those with 4 yr degrees, have succeeded in outsourcing the United States for higher profits that have went in their pockets for the last 40 years. Very little mechanical aptitude is needed anymore as the junk is made unrepairable or uneconomical to repair. Gotta keep GDP up and the lower class down by selling new junk to all the time. It’s no wonder that it’s a dying trait. About the same as Integrity and Accountability for the last 416 years.

Dude I’m on your side on this. My dad was a mechanic, bricklayer, Railroad employee, truck driver and gun smith. Most of my relatives are farmers, linemen, and previously coal miners. I happen to have a degree but ended up serving the military industrial machine, destroying my joints, and helping with regional destabilization on the behalf of those who control the levers (didn’t understand this at the time).

 

[new2solar2]

How long have you had your mrcools? I've seen a ton of mixed reviews and have read Mitsubishi is the gold standard of mini-splits...

First one in June, 2nd in early July. The first Mitsubishi was October 2022, 2nd January 2023. Not long but no leaks and so far good, time will tell.

Do you know what model it is? Hyperheat/non-hyper heat?
Also, are the two on a multi-head condenser or do both have their own?
Thanks!

 

[MajicDiver]

Do you know what model it is?

I’m traveling, will let you know in a few days

 

[LydMekk]

I got 8 Mitsubishi Zen models minisplits installed.
Pure offgrid.
No issues and very low consumption. Perfect for offgrid/batteries.

 

[new2solar2]

I got 8 Mitsubishi Zen models minisplits installed.
Pure offgrid.
No issues and very low consumption. Perfect for offgrid/batteries.

Thanks! I'll check out Zen models.

 

[DaveF]

Mitsubishi is one of the few mini-splits that has true electronic power factor correction which is important when running from a battery powered inverter. Their AC current profile is near perfect sinewave with greater than 0.98 power factor.
View attachment 171810
Good luck on finding another mini-split manufacturer that even specs power factor.

Most cheap mini-splits have just a simple rectifier-filter capacitor which has a terrible high peak current crest factor and a power factor of 0.5 to 0.65. Larger units usually have a filter choke between rectifier and filter capacitor which reduces current peak crest factor approximately in half with a power factor of about 0.8. They only put the choke in to prevent circuit breaker from popping from high current crest factor with the larger btu unit

Thank you! This info about power factors makes this possibly the most useful post about mini-splits that I've come across.

Mitsubishi also seems to have more and better information about about their mini-splits. I'm not sure how many even list a power factor.

 

[zanydroid]

Thank you! This info about power factors makes this possibly the most useful post about mini-splits that I've come across.

Mitsubishi also seems to have more and better information about about their mini-splits. I'm not sure how many even list a power factor.

I looked last night at Gree Livo spec sheet while researching this thread (to see what you get for entry level in the US). All it said was "Power Factor Correction: Yes". I just googled Gree Flexx (competitor of multiposition air handler from Fujitsu and Mitsubishi) and it's the same thing. I guess PFC: Yes is better than no.

FWIW Fujitsu also publishes power factor (just did a quick Google). In fact it gave a separate power factor for heat and cool mode - 0.99 / 0.98 (tryhard)

 

[Jacob89]

Are you guys talking about Mitsubishi Heavy Industries or Mitsubishi Electric splits? Maybe you only get one or the other in the US? We get both and it can cause confusion. Despite the name they are separate companies with their own products.

 

[740GLE]

I remember reading somewhere about the hyper heat models having a very high (200w) idle draw, even when off? I wonder if that's what he means?

I can confirm our Mitsubishi 36k hyperheat 18seer1 with both head units fully off has about 200w idle usage measured via a clamp meter.

Kinda a bummer for an “energy star” unit, but it’s fully on grid so is just another $1/day to the utilty if it sits idle. On the shoulder seasons I try and open the breaker as much as I can.

This is the first year with the unit and going to to the first fall for heat I’m hoping I can run it into mid Nov (low of 30s, high of 40s) before I fire up our wold boiler to properly heat the house and all the rooms.

 

[SilverbackMP]

Are you guys talking about Mitsubishi Heavy Industries or Mitsubishi Electric splits? Maybe you only get one or the other in the US? We get both and it can cause confusion. Despite the name they separate companies with their own products.

Mostly Mitsubishi Electric in the US though I think Heavy Industries are available (???), but you’d need to search hard for them.

 

[MajicDiver]

Do you know what model it is? Hyperheat/non-hyper heat?
Also, are the two on a multi-head condenser or do both have their own?

Photo's of the Mitsubishi and McCool nameplates attached. Each has a single air handler. No hyper heat.

I find interesting the extended discussions of flickering lights potentially being caused by McCool units (and of course other things). I have never had a single instance of flickering lights (when grid tied and also since totally off grid), and I have LEDs from the absolute cheapest they sell at Walmart to high end integrated LED fixtures on multispeed high efficiency ceiling fans. After reading the posts on flickering lights on this thread, I did a little experiment - ran a single MrCool with nothing else but lights on, no flickering, both MrCool's no flickering, then all 4 units, no flickering, then just the Mitsubishi units, no flickering.
In my career installing, starting up, operating and troubleshooting complex utility scale turbine and generator systems my experience has been that typically a confluence of multiple problems is generally the root cause of those types of issues and the vast majority of those are due to carelessness and failure to understand/follow recommendations in the installation, tuning, maintenance and operation of the equipment.
I am sure that there are some very poor low end inverters out there, and I've seen people state that of the Growatt inverters - however, I have growatt inverters and have had no such problems - the couple of issues I had during installation were all my own mistakes (Due in part to limited and poor instruction manuals) and the need for firmware upgrades which does lead one to conclude that the people who tried to use them when they were new products probably had some frustration, which is not unusual for almost any new product.

 

[zanydroid]

Thanks for the experiments.

I think what I find compelling in the discussion is that 0.8 PF is often the worst PF inverters are specced for, but the non corrected minisplits are allegedly well below that (and that is quite believable. I’ve seen plenty of bench measurements showing PF 0.5 on small uncorrected SMPS).

I’ll note that I don’t recall very many people on this thread summarizing their inverter output W and guaranteed PF, nor the W and PF estimate of their minisplit. So we can only conclude weak statements like, the popular sized small minisplit and popular size inverter (3kW or 6kW, like 2-4x headroom) are OK together given how little people are complaining on the forum about minisplits griefing their setup. While daily we see well pump and regular AC complaints and questions about soft starts

So I think it is reasonable to conclude that speccing an inverter not much larger than minisplit max draw is poor design. Since the non matching PF specs of the components (minisplit and inverter) have not been taken into account.

 

[EastTexCowboy]

Missed this thread when it was active but as you've already seen from responses, your HVAC guy is full of it. I'm running three Mitsubishi on the house, a 3 ton and two 2 ton units, plus a 1 ton on the garage. The ones on the house were installed with matching Mitsubishi evaporator units including air handlers so I'm still using the same ductwork but getting all the benefits of the technology. The garage is a regular mini-split. All but one of the 2 ton units run off the solar system and have been since March. Zero problems. Incredible equipment. Where I am in east Texas they don't even include heat strips because the units are 100% efficient down to 4F. With all the units running when it was 110F this summer, along with most of the rest of the house that's also on solar, the highest load recorded in SA was a little over 7kw. They just sip the power instead of gulping it like the old units. Love em.

 

[Warpspeed]

I can confirm our Mitsubishi 36k hyperheat 18seer1 with both head units fully off has about 200w idle usage measured via a clamp meter.

Not familiar with the Mitsu 36k, but some of these heat pumps use a sump heater in the compressor.

The problem this is supposed to cure, is to prevent liquid refrigerant from condensing in the sump of the compressor.
That can completely fill up the crankcase with fluid, and hydro lock up the compressor, potentially burning out the motor which cannot start if the compressor is locked solid.

It depends if the compressor (usually located in the outdoor half of the system) is physically mounted above or below the indoor half of the system, and the relative indoor and outdoor temperatures.
Worst case is having the compressor situated at the lowest point, and freezing outdoor temperatures.
Not that uncommon in the northern US.

If an identical system is installed with the outdoor compressor mounted high up on a wall, or up on the roof, in a much warmer climate, you do not really need the sump heater.
I suspect sump heaters may be mandatory in the US, but probably not so in a place like Australia or Africa.
You may or may not actually need a sump heater, but disconnecting it will probably invalidate the warranty, especially if the motor fails during warranty.

 

[Cardude]

I have a 24k btu Pioneer on 240 and a 9k btu Senville on 120 and both work perfectly on the Growatt.

I’m looking to power a 12k btu 120v Pioneer mini split and looking for some sizing ideas (from someone who has done that) for a van build.

What size Growatt do I need for the van. Everything else will be DC powered except maybe for an AC fridge (if I go that way), TV, occasional coffee pot, and other small appliances.

How much battery capacity do you think I need?

 

[ChrisG]

Nothing to add to the OP original topic, but I'm highly impressed by the Senville 24k Aura (240v). Now that it's getting below freezing temps can really see the power use from my Emporia Monitor->pumped into other tools. Here is a per second view of energy usage when the unit goes from idle to heat. See no reason why most inverters with the right capacity can't handle mini-splits.
›

 

[Brett V]

I’m looking to power a 12k btu 120v Pioneer mini split and looking for some sizing ideas (from someone who has done that) for a van build.

What size Growatt do I need for the van. Everything else will be DC powered except maybe for an AC fridge (if I go that way), TV, occasional coffee pot, and other small appliances.

How much battery capacity do you think I need?

How many watts the inverter is capable of and your battery size is going to depend on your overall load expectations. I've attached a specification sheet for the Pioneer mini splits, showing max watts. You don't have to allow for a startup surge on these units as they ramp up slowly when the compressor is activated.

 

[Cardude]

How many watts the inverter is capable of and your battery size is going to depend on your overall load expectations. I've attached a specification sheet for the Pioneer mini splits, showing max watts. You don't have to allow for a startup surge on these units as they ramp up slowly when the compressor is activated.

I was thinking about this system:

 

[Brett V]

@Cardude That looks good but the video is over 2 years old. I have never done a vehicle mounted system, you will get much better input than I can give you by starting a new post in the Vehicle Mounted Systems section.