[RE-wrenches] mini splits

Thu Mar 13 13:58:34 PDT 2025

Most off-grid homes here in Southwest Florida, one of the most challenging
air conditioning places in the country due to heat and humidity, have moved
to mini-splits. I have a client's system with quad Sol-Ark 15K that is
running eight separate mini-splits and a 4-ton central air unit at a
sprawling residential complex. There are no issues to report. These were
all installed by a reputable local HVAC contractor, so they are not likely
DIY brands. I am not certain about the tonnage, but I believe each
mini-split is 1.5 tons. These are in a highly corrosive/salt environment. I
can't imagine they will last more than a few years each. But from what I
hear, clients on the islands are treating them as disposable in a way. It's
still much cheaper than replacing central air units every few years.

I have another client's system with a single Sol-Ark 15K and it has two
2-ton mini-splits that are DIY by the homeowner. They barely dent the
batteries each day. I see them using as little as 400W to maintain temp in
high ambient heat. Most other clients have single mini-splits. I concur
with one of the earlier comments to stay away from multi-zone if possible.
I don't think there are considerable cost savings anyway, and I have not
been able to detect any energy savings going that route.

There is a guy I did some work for who is running a few old school window
shakers on a Sol-Ark 12K and he has constant problems with surges and
performance of the units. He is in line for a mini-split soon, and plans to
DIY.

Personally, I have a 2-ton DIY cooling my uninsulated garage at home (on
grid) when I need to use it for short periods in the summer. It works like
a champ, and it was dead easy to install. The hardest part was getting the
line set out through the block wall. I think I paid $1,200 for it,
including the trim kit to hide the line set and a wall bracket for the
compressor unit.

I think the bottom line for me is super low startup surge and then fairly
consistent power draw once desired temperature is reached. I feel this is
much easier to plan for off-grid rather than repeated start/stop cycles.

Jason Szumlanski
Principal Solar Designer | Florida Solar Design Group
NABCEP Certified Solar Professional (PVIP)
Florida State Certified Solar Contractor CVC56956
Florida Certified Electrical Contractor EC13013208

On Thu, Mar 13, 2025 at 4:41 PM Wayne Irwin via RE-wrenches <
re-wrenches at lists.re-wrenches.org> wrote:

> Hi Pieter,
>
> I should have said that I "No Longer" vacuum them as the extra step that I
> previously applied made no difference in my experience. We are also in FL.
> with extremely high humidity which might be the difference. Most of the AC
> contractors here confirm the same experience.
>
> That said, they do work well with solar applications.
>
>
> Wayne Irwin
> President
> License #CVC56695
> State Licensed Solar Contractor
> Pure Energy Solar International Inc.
> Wayne at PureEnergySolar.com
> PureEnergySolar.com <http://pureenergysolar.com/>
> SolarChargingStation.com <http://solarchargingstation.com/>
> 352 377-6527 Office
> 352 336-3299 Fax
>
>
> The Sun Is Always Shining!
>
> The content of this message is Pure Energy Solar Confidential. If you are
> not the intended recipient and have received this message in error, any use
> or distribution is prohibited. Please notify me immediately by reply e-mail
> and delete this message from your computer system. Thank you.
>
> ------------------------------
> *From:* pieter offgridenterprises.org <pieter at offgridenterprises.org>
> *Sent:* Thursday, March 13, 2025 4:09 PM
> *To:* RE-wrenches <re-wrenches at lists.re-wrenches.org>
> *Cc:* Wayne Irwin <pureenergysolar at hotmail.com>
> *Subject:* Re: [RE-wrenches] mini splits
>
> Wayne, I saw your post regarding the use of ductless mini splits. I too
> use them extensively, and have an unblemished track record using them. I
> must say that your failures may be in part due to the fact that you do not
> evacuate the system during the installation process. For what it is worth
> the proper procedure is to precharge the system with nitrogen to about
> 200PSI. Then check for leaks and verify the system will hold pressure. Then
> pull a vacuum on the system for maybe 15 or 20 minutes before releasing the
> refrigerant. If you skip these steps you are vulnerbale to diminished
> performance caused by any air left in the circuit, any  moisture will react
> with the refrigerant and turn acidic eventually leading to corrosion. I see
> you keep the lines closed as much as possible but non the less I think will
> find your system longevity will increase, and potentially the performance
> will be better.
> You are getting about ten years so not to bad but I have some healthy
> systems that are 20 years old still going strong.
> Pieter
> ------------------------------
> *From:* RE-wrenches <re-wrenches-bounces at lists.re-wrenches.org> on behalf
> of Wayne Irwin via RE-wrenches <re-wrenches at lists.re-wrenches.org>
> *Sent:* Thursday, March 13, 2025 12:02 PM
> *To:* RE-wrenches <re-wrenches at lists.re-wrenches.org>
> *Cc:* Wayne Irwin <pureenergysolar at hotmail.com>
> *Subject:* Re: [RE-wrenches] mini splits
>
> Hey Jay,
>
> I live off grid (25yrs) in North Fla. (temp range is teens - 100+ F) with
> mini-splits throughout the house (2,700sq').
> I have used just about every brand. We primarily use them for cooling but
> also use heat to supplement the wood stove.
> I can't imagine living without them. Although it's a love/hate
> relationship.
> My experience is that you get about 10 years max from whatever brand you
> buy. Typically, the inside unit corrodes from condensation and leaks out,
> or the outside unit reversing valve locks up in cold or heat position. IMO
> They are not worth repairing. We currently have 4 - 1 Ton units and 1 - 2
> ton. I only buy 1 to1 systems vs 1 -4 as it offers redundancy. I initially
> tried "reputable" brands which typically cost more but have since migrated
> to whatever is the cheapest.
> That said I like Gree and/or the knock off brand that they make (good for
> the price and holding up well). When I am in need of more than one, I
> always buy an extra to swap out whichever unit dies first.
> Fortunately for me, years ago, I had a buddy show me how to install them.
> Pretty simple. They come pre-charged and can typically handle up to 30' of
> line with no issues. If possible, find someone to show you once.  YouTube
> will offer many WRONG ways to do it videos.
> I don't use the vacuum on the lines. I just keep the lines plugged and dry
> until I hook them up.
>
> My 15kW array with 2 - VFX3648R's has had no issue powering any of them.
>
> I hope this info helps.
>
> Wayne Irwin
> President
> License #CVC56695
> State Licensed Solar Contractor
> Pure Energy Solar International Inc.
> Wayne at PureEnergySolar.com
> PureEnergySolar.com <http://pureenergysolar.com/>
> SolarChargingStation.com <http://solarchargingstation.com/>
> 352 377-6527 Office
> 352 336-3299 Fax
> 352 316-1637 Cell
>
> The Sun Is Always Shining!
>
> The content of this message is Pure Energy Solar Confidential. If you are
> not the intended recipient and have received this message in error, any use
> or distribution is prohibited. Please notify me immediately by reply e-mail
> and delete this message from your computer system. Thank you.
>
> ------------------------------
> *From:* RE-wrenches <re-wrenches-bounces at lists.re-wrenches.org> on behalf
> of Michael Morningstar via RE-wrenches <re-wrenches at lists.re-wrenches.org>
> *Sent:* Thursday, March 13, 2025 11:05 AM
> *To:* RE-wrenches <re-wrenches at lists.re-wrenches.org>
> *Cc:* Michael Morningstar <mjmorningstar at gmail.com>
> *Subject:* Re: [RE-wrenches] mini splits
>
> I'm interested in this too
>
> On Thu, Mar 13, 2025 at 7:39 AM jay via RE-wrenches <
> re-wrenches at lists.re-wrenches.org> wrote:
>
> HI All,
>
> I have been getting a lot of questions about people wanting to install
> mini splits in their off grid homes, and in normal homes.
>
> The line of questions usually involves DIY vs contractor.  Of course the
> price difference is staggering, roughly 5X more for contractor.  And I’m
> being asked all sorts of questions about the DIY versions.
>
> Is there a good place for information so I can educate myself as to the
> different brands etc
> Or maybe someone can contact me off list if they have some info to share.
>
> Thanks’
>
> jay
>
>
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