Can anyone think why not mini-split portable?

[CWO4GUNNER]

In the Navy one of my many jobs was to assembled high pressure synthetic rubber hoses some steel braided of every size and type for high pressures ranging from 120 psi to 4000psi working pressure. Lines had to be flexible to accommodate moving hydraulics and robotics in the worst of conditions.

So why hasn't anyone come up with a mini-split portable system using high pressure flexible braided lines. Imagine how easy and seamless window accessibility would be and the benefits and uses a potable high efficiency unit like this could offer to the landlord or HVAC service technician in emergencies who's customer central unit has failed in the middle of a heat wave. Not to mention ease of installation compared to other window units.

 

[CWO4GUNNER]

Well I got my answer. Someone on another forum was kind enough to point me in the right direction. Unbeknownst to me portable mini-split flex line units already exist but at a huge proprietary price http://www.amazon.com/dp/B0083ITX7W/?tag=atomicindus08-20.

As a landlord with tenant central AC systems that could fail at a moments notice, something like this for emergency use could save me serious money form having to be at the mercy of contracted emergency repairs, and buy me time for off season DIY repairs/new installation when time is not a constraint. Now that you've armed me with this information, once I get my garage mini-split DIY installed, Ill start research work on what houses will work and have them made or assemble them myself. Who know, there might even be a market for retrofit resale.

 

[DEnd]

Your basic idea has some merit. However you are typically only looking at a few days at most use per client. For example a co-worker recently lost her air conditioning, and decided on getting a new system installed. She was only out of A/C for 4 days. If she had decided to repair her system she would have only been out of A/C for two days. To get her decent A/C for that time period would have likely required 3-4 units, which could have strained her wiring in the house. Basically the set up time for something like that would likely be about the same as repairing the system, and rental costs would likely be about the same as well. That said it could be a decent idea if the systems could be installed by untrained homeowners or temp workers, but it's not something a HVAC service company would likely want to divert their HVAC techs to install.

 

[theoldwizard1]

In the Navy one of my many jobs was to assembled high pressure synthetic rubber hoses some steel braided of every size and type for high pressures ranging from 120 psi to 4000psi working pressure. Lines had to be flexible to accommodate moving hydraulics and robotics in the worst of conditions.

So why hasn't anyone come up with a mini-split portable system using high pressure flexible braided lines.

$$$ !

 

[yeldogt]

In many parts of the world they use refrigerant tubing -- like in an automobile. With quick connects for the refrigerant lines .... so somewhat portable


the portable ones pump cold water -- all the refrigeration is outside -- they are using the cold water in a fan coil

 

[CWO4GUNNER]

Your basic idea has some merit. However you are typically only looking at a few days at most use per client. For example a co-worker recently lost her air conditioning, and decided on getting a new system installed. She was only out of A/C for 4 days. If she had decided to repair her system she would have only been out of A/C for two days. To get her decent A/C for that time period would have likely required 3-4 units, which could have strained her wiring in the house. Basically the set up time for something like that would likely be about the same as repairing the system, and rental costs would likely be about the same as well. That said it could be a decent idea if the systems could be installed by untrained homeowners or temp workers, but it's not something a HVAC service company would likely want to divert their HVAC techs to install.

Well I have been a landlord now for 10 years after retiring from the service in 2004 in which my specialty was mechanics, hydraulics, and electricity. I got graduated and got my universal HVAC in 2012 to save money on rental unit HVAC contracted repairs. It was the most immediate cost savings investment I have ever made (huge $$$$). Now looking toward the future at aging central units Im planning on phasing out the use of traditional central AC ducted systems and self installing VFR mini split dustless systems, a trend that is sweeping the nation. In order for me to save the really big bucks, I need to come up with a very effective portable system that will allow me to legally postpone maybe for months, the installation of a permanent whole house mini-split system without relying on an outside contractor, huge savings $$$. This due to the fact that my rentals are located in one of the hottest summer climates in the world 100-125F things have to be cool the same day things brake even though legally Im not required to take any action for 2 weeks, that would be evil. So the dots are crystal clear here NOT crystal ball, all I need to do is get those dots connected this fall in preparation for next summer season. Sure the investment to set up a portable 30K btu mini-split system with flex hoses will cost me about $2500, but providing me the flexibility to DIY install a permanent system, probubly recycling the portable will save me tens of thousands over the course of phasing in all my other rentals. Its all upside and good for business. I even read an article about the US market for mini-split ductless VRF systems from Asia is growing at an alarming rate, due to their flexibility and ease of installation. In fact it is predicted by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers that by the year 2018 only small portion of new construction will account for traditional central ducted systems.

So in summery the older traditional systems are being left for dead in the attic. The DIYer didn't kill them. Don't blame the DIYer. They were marked for death before we got here. You know why? New technologies and obsolescence.

 

[DEnd]

So in summery the older traditional systems are being left for dead in the attic. The DIYer didn't kill them. Don't blame the DIYer. They were marked for death before we got here. You know why? New technologies and obsolescence.

VRF isn't just limited to ductless systems. You can get many of the benefits with a ducted system as well. Toshiba has VRF for high static pressure ducted systems from 1.5 tons on up. LG has high static pressure systems from 1 ton on up. Considering you are looking at retrofitting these systems continuing to use a ducted system may be a better option for you than installing multiple heads in each of your units.

 

[pseudorealityx]

You're getting a little ahead of yourself on VRF taking over the world. There's lots of stuff that VRF cannot do, at least with what's available commercially today in the USA.

How are you going to power your portable 30k BTU unit? You need a 208v/1 power supply, not just something you can plug into the wall.
What are you going to do to distribute the air? Maybe your units are tiny little things?

 

[CWO4GUNNER]

Considering you are looking at retrofitting these systems continuing to use a ducted system may be a better option for you than installing multiple heads in each of your units.

Single system-multiple head; Multiple system-single head....As long as I no longer have to crawl in that attic nor work out load distribution, velocity, assemble and maintain ducted systems in hot attics that account for 30% of heat gain. And don't tell me that the new metal round ducting looks great inside the conditioned space giving the home that new industrial look. I'm telling you its over, the horseless carriage is finally arrived, long live ductless systems.

 

[CWO4GUNNER]

How are you going to power your portable 30k BTU unit? You need a 208v/1 power supply, not just something you can plug into the wall.What are you going to do to distribute the air? Maybe your units are tiny little things?

Uh-Oh Ya think so, no kidding....Come on give me some credit, a breaker and some 3/10, and a few ceiling fans. I don't know why suddenly so many are defending duct-work. when I did contract I couldn't even get a technician to go in a hot attic in summer to take a look, but they would try and charge me for a system leak assessment ($500) without going up there. Wasn't part of there job or they weren't allowed, remember I was told these things before I got certified.

However I will tell you that even though I don't need to I will be using the remainder of my "Post 911 GI Bill" to get my residential electrician certification at the local community college starting next spring, provided that I can pass the compass test for basic algebra. I only have until 2020 to use it up and I have about 25 credits left which includes housing allowance $1200 a month. So I gotta use it all up anyway, I just hate the hand math.

 

[over40pirate]

I have 1 rental, and will have 2, when we move into newer house.
If one of my AC units quit, I will try to fix myself. And was thinking of getting my License.

When it quits, if I can't diagnose and fix in 1 or 2 days (90 degree/80% humidity) I would buy a 14,000 btu portable ac. This will give some relief. Might even offer a few fans. Can't see anything elaborate, in advance.

My luck when I finally needed it, it would have leaked out the refrigerant, and now out of warranty! Buy when needed on something like that.

 

[CWO4GUNNER]

I have 1 rental, and will have 2, when we move into newer house.
If one of my AC units quit, I will try to fix myself. And was thinking of getting my License.

When it quits, if I can't diagnose and fix in 1 or 2 days (90 degree/80% humidity) I would buy a 14,000 btu portable ac. This will give some relief. Might even offer a few fans. Can't see anything elaborate, in advance.

My luck when I finally needed it, it would have leaked out the refrigerant, and now out of warranty! Buy when needed on something like that.

I was in your shoes 2 years ago. Do your self a big favor and find a community college (way cheaper) that has a good HVAC certification program. There are too many things on the electrical side that are easy to fix if your schooled. Believe me the investment will probubly pay for your tuition before you graduate, at least it did for me. Not to mention the classes are fun with allot of cometary...

 

[over40pirate]

I have 1 rental, and will have 2, when we move into newer house.
If one of my AC units quit, I will try to fix myself. And was thinking of getting my License.

When it quits, if I can't diagnose and fix in 1 or 2 days (90 degree/80% humidity) I would buy a 14,000 btu portable ac. This will give some relief. Might even offer a few fans. Can't see anything elaborate, in advance.

My luck when I finally needed it, it would have leaked out the refrigerant, and now out of warranty! Buy when needed on something like that.

 

[theoldwizard1]

Single system-multiple head; ...

I see this as the future. These systems are complex with all the valving, but Mitsubishi (likely the leader in mini-splits) seems to have it worked out.

Retrofitting a typical 3 bedroom house would be difficult running refrigerant lines and would likely require 2 single system-multiple head units (upstairs/downstairs). $$$ !

On new builds, the biggest issue will be providing heat for the coldest days of the year (the entire midwest and notheast frequently see below zero). The obvious solution is geothermal, but then the cost are doubly huge !

 

[CWO4GUNNER]

I see this as the future. These systems are complex with all the valving, but Mitsubishi (likely the leader in mini-splits) seems to have it worked out. Retrofitting a typical 3 bedroom house would be difficult running refrigerant lines and would likely require 2 single system-multiple head units (upstairs/downstairs). $$$ ! On new builds, the biggest issue will be providing heat for the coldest days of the year (the entire midwest and notheast frequently see below zero). The obvious solution is geothermal, but then the cost are doubly huge !

Well I cant speak for the rest of the country, but here in the Southwest/West is where most of the industry shift toward ductless mini-split systems will probubly take place. Especially here is the deserts where the properties are larger and homes are single story, and where our winters are so mild we don't turn our furnaces on but for a few days in winter. Some of the new systems are 50,000 BTUs have 7 heads, and why go through dry walls to show your lines when its easier to run your lines and controls through the attic and just drop them down between the wall studs a few inches, no problemo amigo..

 

[DEnd]

Single system-multiple head; Multiple system-single head....As long as I no longer have to crawl in that attic nor work out load distribution, velocity, assemble and maintain ducted systems in hot attics that account for 30% of heat gain. And don't tell me that the new metal round ducting looks great inside the conditioned space giving the home that new industrial look. I'm telling you its over, the horseless carriage is finally arrived, long live ductless systems.

LOL I'm as much of a fan of ductless as anyone, but as this is a business expense for you, you should consider all the options. That said multiple heads may be the best option for your renters and you if your ducts are in an uninsulated and unconditioned attic. You may want to price out insulating the attic and turning it into conditioned space and compare it to multiple heads. Even if you go the multiple head ductless mini-split route you should consider making sure the attic space has a good airseal between it and the rest of the house/units. This along with proper insulation levels will help your renters reap the benefits of mini splits via a lower electric bill, as well as help ensure the unit is comfortable for them.

 

[DEnd]

On new builds, the biggest issue will be providing heat for the coldest days of the year (the entire midwest and notheast frequently see below zero). The obvious solution is geothermal, but then the cost are doubly huge !

Some mini splits provide useable heat down to -13F, so don't count the Midwest and the northeast out.

 

[pseudorealityx]

Uh-Oh Ya think so, no kidding....Come on give me some credit, a breaker and some 3/10, and a few ceiling fans. I don't know why suddenly so many are defending duct-work. when I did contract I couldn't even get a technician to go in a hot attic in summer to take a look, but they would try and charge me for a system leak assessment ($500) without going up there. Wasn't part of there job or they weren't allowed, remember I was told these things before I got certified.

However I will tell you that even though I don't need to I will be using the remainder of my "Post 911 GI Bill" to get my residential electrician certification at the local community college starting next spring, provided that I can pass the compass test for basic algebra. I only have until 2020 to use it up and I have about 25 credits left which includes housing allowance $1200 a month. So I gotta use it all up anyway, I just hate the hand math.

I'm defending duct work because it's a better system to distribute air in a broken up residential floor plan. Having multiple heads everywhere is expensive and ugly.

 

[CWO4GUNNER]

Having multiple heads everywhere is expensive and ugly.

Yeah your right, Iv been thinking of using the existing central register locations to install the ductless cassettes. That way no one will ever know the difference and no ducted head gain. Two birds with one.

 

[pseudorealityx]

The ductless cassettes don't have enough static to push though much of anything.

You can get ducted versions, but even they are limited on airflow and static. You need to be really careful with the duct design to get the flow you want.

 

[CWO4GUNNER]

Wow...was out Sup-bording today on lake Mohave and got a little weather beaten, then came home made a steak and passed out. When I woke up at 7:30 couldn't believe I slept all night (great swamp cooler), but starting to make coffee noticed it was still dark out. Ah! Its actually 7:30 PM...

Oh, as I mentioned, humidity levels are dropping beck down this week to the teens. So I switched off the AC and started my Brisa 5000 cfm swamp cooler back up this morning. When its really dry there is something very refreshing about a swamp cooler an AC just can't replicate, especially the fresh air.

Oops off topic....yes after the bottom fell out with the last recession 2008- present, no more unnecessary debt for me. Too-expensive or not, anything big-ticket when it comes to labor cost, I will DIY. AC, electrical, plumbing, gas, auto mechanic, appliance repair, taxes, landscaping, carpentry, flooring installation.....When it comes to businesses discrimination, I'm an equal- opportunity DIYer....

Fully awake now I can see by the subject line that Im still off my own topic. OK then, after much thought and consideration, I will most likely stick with "window AC" when it comes to emergency portable AC when my rental units AC break down. But I sure hope that one of this low cost muni-split companies develops a portable, or Asian AC parts supplier starts selling flexible hose kits for them becasue I really do think a low cost portable mini-split would make the ultimate pop-in and forget window unit.