Mini Split Install

[glennm]

Hi:

I am going to be installing a 12,000 btu senville mini split and I have a few questions. This will be for a loft over my garage, the garage has heating (radiant tube) and the loft is an extra space (650 sq ft with 10 ft vaulted ceiling) and will be used if we have visitors that wish to stay for a couple of days.

I plan on running the line set down the inside wall and this will be a fairly straight run to the outdoor unit. I will mount the outdoor unit on a bracket.

I am comfortable with the install, including the electric but I'm not sure what to do about vacuuming the lines. I called around and nobody seems interested in doing the work unless you pay up and buy the unit from them at (as you know) a considerable markup. I am thinking about getting a pump and gauges from Amazon and doing it myself? This looks like a fairly simple procedure? Thoughts?

Also, do you need a GFI for the disconnect? It doesn't look like you do but i thought I would ask.

Thanks in advance, I will document the install once the unit arrives. (should be a couple of weeks from now)

 

[Git]

I bought a Mr Slim unit from an internet vender and installed it myself but before I placed the order I lined up two local contractors to 'commission' it (getting it up and running). It's a good thing I found two, because when it came time to actually use them, one of them cancelled on me.

This was several years ago and they visually checked everything over, used nitrogen to check for leaks, vacuumed down the system and release the Freon. I paid $300 and it was basically to validate the warranty on the system.

You also have some other options - buy one of the DIY systems where the lineset is already pressurized or look into buying the proper equipment which at the time would have been around the $300 range for me. In retrospect I was worried about the warranty, but I would probably have been better off just doing everything myself

 

[830singleshot]

I did a 12 k Pioneer mini split a few months ago. I bought the flaring tool, gauges and vacuum. About $200 for the tools. The only thing I didn't do a pro would is pressure test the lines with nitrogen.
I practiced several times cutting and flaring until I had confidence in the flares and used Nylog. In my opinion, my work was nicer than someone who has to bang out jobs for a living. Extra time to make it perfect was not a issue. Job turned out perfect and I'm thrilled with the final result. Your results may vary based on your skill set. JMHO

 

[glennm]

This is what I’m thinking. There is a kit on amazon for a couple of hundred bucks, I don’t need to do any flaring, the length of the line set is about right and it goes through a crawl space so I can leave any excess in there, some sealant and done?

 

[Terry D]

Its not hard to do, its following procedure. Sometimes, really more a lot of times, those factory flares are not worth a **** on some units. This is where you will have problems right off the bat or down the road. I would inspect those factory flares and possibly cut them off and do your own. As far as buying all the stuff to do it for 200 to 300 dollars, I have read on here people buying those kits and having good luck. Personally, just my vacuum pump cost more than that. But I get it, why spend a crazy amount of money only to use it a couple of times.

Starting with the 2020 NEC, that mini split would have to be GFCI protected, dont know if your state has adopted it yet. In fact, all 240 volt appliances will have to be GFCI protected, which I think is crazy, but being a licensed electrician, I have to follow the rules.

Remember, you can not leak test with a vacuum pump. You will need to pressurize the system with nitrogen to do it right. But that will cost another 150 to 200 to by that stuff. Here is a link of a guy on youtube that is very knowledgeable, but he does this for a living and his tools are expensive, but he explains it very well

 

[Git]

I thought the flaring was actually pretty easy and that way you don't have a lot of extra tubing coiled up somewhere. I bought this flaring tool on Amazon (it was $103 when I bought it) and made sure to use Nylog on the flares when tightening them done. From what I understand it helps lubricate the flare and prevents cracking from being rotated/torqued


Regarding pressure testing, I was going to add on to my system but decided not to. I was able to take one of my smaller CO2 tanks to my local gas distributor and they filled it with nitrogen for me. All I needed was the proper regulator line to connect and it would be good to go. ended up wasting the nitrogen on our tires and other stupid things like that


Good video on the flaring tool

 

[Terry D]

Its ok to apply a very small amount of Nylog to the flare surfaces, and some say that is not good, but never to the threads. It will make you over torque it, resulting in a leak

 

[rebelranger]

Just a tip. Install the system call a local hvac tell them it stopped blowing cold or hot air, season defendant and you believe the refrigerate leaked out. They will come inspect, leak test, and get the system running for you. Then tell them some non local company did it and you just knew the deal was too good to be true. I've done this method for three mini splits I've installed. Each time it's been $150 for inspection and releasing the refrigerant. I do believe the contractor caught on the third time though lol.

 

[glennm]

Its ok to apply a very small amount of Nylog to the flare surfaces, and some say that is not good, but never to the threads. It will make you over torque it, resulting in a leak

I just watched a YouTube video and the guy put nylog on everything. Thanks for the tip!

 

[jjrbus]

Keep in mind the bulk of installs fail because of improper installation! Many of the how to videos are either for R22 or done by people that do not have a clue what they are doing!!

I checked the ready made flairs with a flair gauge and I think 3 of them failed and the nuts on the ready made sets are too light.

Installing a mini is not rocket science, but requires proper tools and procedures. Is not a bailing wire and duct tape job. Need the right tools or greatly increasing your chance of failure.

 

[glennm]

Well, the unit arrived. Looks good and I will figure out the path for the line set this weekend. I’m not sure of the wire size, the manual says 1.5 wire, the breaker is a double 20 so I assume 12 g wire? I have a bunch of 14 here but I assume that’s too small? I will run the wire in emt to the shutoff, only about 6 or 8 ft to the unit.

 

[jjrbus]

Not an electrician but have done lots of wiring over the decades. I would say that I have never heard of 1.5 wire but have spent time in Asia. 1.5 mm wire is AWG 16. I do not know if Canadians use metric wire size?

One of the reasons I stayed away from the off brands is the directions cause people lots of headaches and even the pro's don't want to get involved in deciphering what they mean.

 

[Notgrownup]

Go to a local supply house for refrigeration and ask the counter guys if they know somebody who works independently.

 

[justinjoyal]

Im pretty sure that unit needs a 15amp circuit, but if the breaker you have installed is 20amp then you need 12awg wiring.

Run pvc 14awg stranded wiring between the indoor and outdoor unit.

One of the reasons I stayed away from the off brands is the directions cause people lots of headaches and even the pro's don't want to get involved in deciphering what they mean.

That’s a Midea. Hardly off brand considering the number of units they manufacture worldwide but I know what you mean. [emoji6]

 

[LS6 Tommy]

Just FYI, if the loft is open to the rest of the garage it's not legal. You can't have "open" dwelling space in a garage. It has to be a separate, walled space.

Tommy

 

[glennm]

No, it’s not open to the garage. It’s also not a living place, just finishing it. I may use it as a place to sit around during work breaks. Don’t know for sure but the cost of the mini split is low if I can do it myself

 

[glennm]

I called the supplier today to confirm the electrical requirements and they told me the unit is rated for a double 15 breaker and will run just fine that way but —- they recommend 20a ?

I have everything for the 15a run so maybe I will just do that?

 

[justinjoyal]

I called the supplier today to confirm the electrical requirements and they told me the unit is rated for a double 15 breaker and will run just fine that way but —- they recommend 20a ?

I have everything for the 15a run so maybe I will just do that?

Yes 15a is fine.


Envoyé de mon iPad en utilisant Tapatalk

 

[jjrbus]

The breaker protects the wire, there should be a data plate on the unit showing amp draw. A quick peak at the Senvil site shows max 15 amp max fuse for units similar to yours. So do not know why you would be told to use 20A? The 1.5 or 16 AWG refers to the communications wire between units.

 

[glennm]

I will use the 15a and 14 wire. I was confused as to why they suggested 20a. Should have it done this weekend and then I either get a pump and gauge set or find someone to do it for me

 

[karoc]

Sounds like your at minimum wire size,if a fan motor or compressor should lock up the wiring may damage some before the breaker trips or if it happens several times or if you should lose a leg of power. Should be a name plate with the RLA on it. How much more money would it cost to go with 12ga vs 14ga, does not mean you have to go with 20amp breaker

 

[Notgrownup]

I believe I used 10 or 8 ga wires. I just ran it for that specifically to a disconnect outside.

 

[glennm]

Got the outside unit installed, line set is in place, now I need to mount the inside unit and the disconnect. So far it’s relatively easy

 

[glennm]

Disconnect done. Waiting for a breaker to complete the electrical. Tomorrow I will mount the inside unit and see if I can find someone to test and evacuate the lines

 

[justinjoyal]

Looks good.

Next time mount the outdoor unit on the concrete foundation. [emoji6]

In your situation, definitely use pads between the legs and the wall to absorb some of the vibration.

 

[Phuckin' Jim]

Hi.
Did you get your installation completed yet?

 

[glennm]

Everything is done except vac the lines. I called around a bit and still no one to do the job. I’m tempted to try it myself. I will look around a bit more and see if I can find someone. The installation was fairly easy. I have very little extra line set, maybe just about 16”

 

[Phuckin' Jim]

There are cheap vacuum pump and guage sets on Amazon.
I ordered one for about $150 or so.��

 

[Phuckin' Jim]

The one I ordered is no longer available, but I found this one:

https://www.amazon.ca/dp/B07D6K297V/?tag=atomicindus04-20

You'd likely be able to sell it on Kijiji for most of what you paid for it once you are done with it.

 

[glennm]

Yes, that would be what I would do if I can’t find someone to do it for a reasonable price. It really doesn’t look too difficult?

 

[glennm]

The one I ordered is no longer available, but I found this one:

https://www.amazon.ca/dp/B07D6K297V/?tag=atomicindus04-20

You'd likely be able to sell it on Kijiji for most of what you paid for it once you are done with it.

Are you fairly confident that doing it yourself would be easy?

 

[Notgrownup]

I opted to mount my condenser unit on the ground because I didn’t want the vibration in the wall.

 

[rebelranger]

Recall my previous post how to get hvac techs to help just charge the system

 

[glennm]

I took the advice of someone here and called an hvac supplier. I asked if they knew someone that would come out and do the lines for me. The person handed the phone to one of the employees and he is coming out in a day or two for an hourly rate. It should cost me about half of what the equipment would cost.

I’ll update this when complete. I’m excited to see how well this works!

 

[Phuckin' Jim]

What part of Ontario are you in?

 

[glennm]

Cambridge

 

[Phuckin' Jim]

The heat pump should easily keep the room warm this winter.

 

[glennm]

Hoping so, should find out soon

 

[Phuckin' Jim]

Install looks good so far.

 

[Phuckin' Jim]

From what I remember about southern Ontario, you'll really appreciate the A/C too!
Spent a summer near Wallaceburg several years ago.