Mini Split = Who has done DIY Install

[mobiledynamics]

I guess if you hang the compressor out outside close to the indoor, it should be more straightforward.

For those that have DIY'ed mini-splits, how cut-N-Dry was it for you.

I have had 3 mini-systems installed in the 3 houses I've owned. 2 Mitsub, 1 Daiken. All more of a complex setup - with compressors all out of sight, long lineset runs, etc. I could never had DIY'ed them.

With the recent threads, I just wanted to post and see who has.
I'm quote amazed at *how much* I'm paying for the total installed cost relative to just what the internet pricing is on these units alone. Assuming if I'm going the installed route, aside from the labor costs, there is profit on the units..we're talking 3-4X.


I could see myself running the linesets, mounting the compressors, running wire - but I would still hire out someone to make the connections, purge the lines, check the charge, etc, etc

 

[nmcqueen469]

Very interested in this as well.

 

[mobiledynamics]

And for all you DIY'ers, are you guys running the *electrical* with the disconnect and putting a 120 outlet there for the *service guy* should he need his vac and such.

Alot of fine details that even me, a tool ***** , may not attempt to under-take except maybe for a garage or shed, where if I F'up or do a sub-standard job...it would be be part of the *home*.

 

[ghnl]

I installed two - one in the garage, identical one in the 'bonus room' above. Electrician installed the outside boxes that have a HD switch inside. I ran the line sets making the connections then I hired an HVAC tech to evacuate the lines and open the valves.

I easily saved $3000 by DIY. Info/pictures here: eL-cheapo line set covers

 

[acer66]

Very good idea with the line set covers, it is crazy how expensive they are.
If you have an existing set up you could use pvc rain gutters, I guess.

 

[whatuusay1]

I installed mine as well - very easy if you read the manual. I purchased my LG unit around $1,600 from acwholesaler, I didnt bother with quotes from HVAC companies. From seeing the quotes that some guys are getting i wouldn't bother - you can easily save 50-75% off what they are charging. Its a very easy install in my opinion, its a 4-5hr project. I didnt attempt the lineset connection myself. I paid an HVAC company to do it ($130-150 if I remember correctly).

Here's my build log -> http://www.garagejournal.com/forum/showthread.php?t=121344

I ran the lineset and drain in the wall for a cleaner look. If you have any questions just ask.

* Edit - I did do a disconnect as required by code - I didnt put in an outlet out there (I have an outlet nearby on the deck for any tools).

 

[my02v6]

I hope this thread becomes massive. This is an area with high interest nowadays.

 

[nonhog]

I like where this is going. I don't mind rolling up my sleeves and getting dirty.

 

[mobiledynamics]

I'm no HVAC tech. Maybe one will chime in.
When is the max length between the 2 good for charge that comes with the unit versus additional length due to lineset install.

Brazing capabilities

Checking the Charge

Electrical *best pratices*. There is probably 10 different ways to run it. Both from a primary and also on the controls.

For me, with all the above that goes on, I would rough it, pull the linesets and the wiring, but let a electrician do the wiring and a HVAC tech to do hookup & connections.

 

[estrellajon]

I'm in the process as well for the garage. Will be attempting the install on my own and hire AC guy for charging.



Sent from my DROID RAZR

 

[jad3675]

I'm doing a mini-split install at my house - bought the system over the intertubes, and am doing 90% of the work myself. Local installers wanted upwards of $10k to do half my house - I'm in for a hair over $5K doing all the work myself. I'm not using the traditional wall mount units, I went with the concealed cassette models, and am running individual duct work to the rooms.
Between work and family, I have about 5 hours on Sunday that I can actually do any work, so the install has been a little....slow. I should be done in the next two weeks though. I hope to get all of the linesets run this weekend, and perform the pressure test and vacuuming the following weekend.

This thread is a pretty detailed look at a MS install.
http://ecorenovator.org/forum/geothermal-heat-pumps/683-sanyo-24khs72-ac-hp-diy-install-project.html

John

 

[mobiledynamics]

Congrats John. Are you also going to do the seperate wall controls versus the *remotes*. What brand. I'm a huge fan on Mitsubishi and Daiken. The last time I used cassesssted - the 2nd home I owned, the casette footprint was huge. It took a little work but we got a plan on getting them to fit by dropping the ceiling...and re-rocking.

 

[RKA]

I'm no HVAC tech. Maybe one will chime in.
When is the max length between the 2 good for charge that comes with the unit versus additional length due to lineset install.

Brazing capabilities

Checking the Charge

Electrical *best pratices*. There is probably 10 different ways to run it. Both from a primary and also on the controls.

For me, with all the above that goes on, I would rough it, pull the linesets and the wiring, but let a electrician do the wiring and a HVAC tech to do hookup & connections.

If you search the forums, you'll find nuggets of info that DIYer's (including myself) posted. I spent several nights reading that very same thread on ecorenovator. Very nice guy and he took the time to call me to make sure things were progressing okay on the day of the install.

Specifically addressing your questions:
Charge is based on weight. The manual will state minimum lineset length (if any), the length of lineset the pre-charge is good for and an ajustment that can be applied for every foot of lineset outside the length of lineset the pre-charge was good for. So read the manual before you purchase so you're clear. If you need to add or remove, this is where it's most practical to call a tech to adjust the charge before you turn it on.

Brazing isn't usually done. Any presence of air during the process will create some corrosion over time that will lead to contamination of your system. If you flowed nitrogen through the linesets and were well versed in the process you could do it. The other issue is the high pressures used in these systems. A connection might not leak at 300psi that you might see on yesteryears systems, but it will once you get to 500+ psi on your minisplit. Alternatively, use flared connections (which is what the factories typically intend for you to do). If the flares are well made and adequately torqued (not overtorqued) they will seal well. There are linesets coming out of the indoor unit with flares and nuts on them. Some advise cutting the factory flares and creating your own. That's up to you. You'll need to flare the linesets you buy that will run to the outdoor unit (or buy pre-flared ones). Many advise to flare them yourself. Personally, I flared them myself using a yellow jacket tool that was darn near idiot proof and produced very nice flares. It was expensive, but so is hiring someone, so that was that. There are cheaper tools out there, but they may require some practice to get the hang of. Not a big deal. Regardless of whether you do it or a tech does it, make sure you do a standing pressure test with nitrogen. The manual may even state that you should test to 300 psi before pulling the vacuum. Most skip this step and go straight to the vacuum and once they pull a vacuum, close everything off and make sure it holds. I was in no rush to finish, so I did both for good measure but there was a cost for the nitrogen tank and regulator.

Checking the charge - already answered. Do by weight.

Best practices for electrical - not sure what you're asking. Read the manual. Most will tell you the amperage draw and most will require a line to the outdoor unit with appropriate gauge wire. In my case it was a 30A breaker, which requires 10 ga. wire (the manual will tell you to size to code, but ask here if you're unsure about gauge size). The manual also stated I needed a 16 gauge 3 wire cable for power and control between the outdoor unit and indoor unit. Get something outdoor rated. Put a disconnect box within reach of the outdoor unit and use water tight conduit and connections from the disconnect to the outdoor unit. So when you're done, the wire routes from electrical panel --> conduit --> outside disconnect --> outdoor unit --> indoor unit. That will cover most installs, but read the manual, they will clarify. And it's an installation manual which is different from an operational manual.

 

[mobiledynamics]

On the flare....
The techs that have done the installs on mine, always have brazed them. I can't really all the details but it was just interesting watching them do it. I remember asking them why they weren't using couplers instead of just crimping a larger one on it and then brazing th beejeezus out of it.

 

[jad3675]

Congrats John. Are you also going to do the seperate wall controls versus the *remotes*. What brand. I'm a huge fan on Mitsubishi and Daiken. The last time I used cassesssted - the 2nd home I owned, the casette footprint was huge. It took a little work but we got a plan on getting them to fit by dropping the ceiling...and re-rocking.

I went with Fujitsu, they seem to have a better local presence with the contractors. I could not find a Daiken installer in my area, and the closest Mitsu guys were 3 hours away. Yes, separate wall controls. I have a cape cod style house, so I've been able to conceal the cassettes (26" x 24" x 7", 40lbs) in the knee wall space. It would have been far cheaper and less time consuming to do the wall mounts, but our main living room would have been impossible to mount one in easily.

So, like RKA I spent more than a few bucks on a nice flare tool, tubing cutter, reamer, vacuum guage, manifold set and a nitrogen regulator (though I plan to use argon, because that's what I have handy. Inert gas is inert gas, right?). I have the east side of the house to do next year, so I'll just save the tools.

I had to have custom transitions made for the concealed units - local guys wanted $60/each to fabricate them. The Ductshop.com out in CA did them for $45/each shipped. I found it cheaper to buy 25ft of R8 flex duct and just rip out the flex than it was to buy 25ft of R8 insulation.

It's been an experience. If I had more free time (or took vacation from work) I could have had the installation done in a week. However, sweating my *** off for 6 weeks has definitely been worth the $5k I saved.

John

 

[slowpoke]

Very timely thread for me. Have a friend who just installed a Mitsu Mr Slim. He already had the electrical in place and had a HVAC guy do the final connection on hoses. Otherwise he installed it himself. I am planning on ordering the same unit myself on Monday. I certainly expect to do my install also. Have a son who is an electrician so I have that covered.

 

[Jackfre]

RKA is on the money here. Skipping the nitrogen purge is bad practice. Blowing the line set out with nitrogen gets all the contaminants out...well most of them. As well, having the nitrogen purge makes it easier to pull a good vacuum.

Brazing is ok, but you have to be good. Really good. Some of the line sets are only 1/4". You get just a tad of silver solder into the tubing and you are screwed. Maybe not today. Maybe only when your warranty is over. I had a good dealer who insisted upon brazing line sets. He had an inordinate amount of failures. He also would not listen and finally switched from my line, Fujitsu, to Mitsu, where I have heard he is having the same problems. Fujitsu's (whom I represented for about 12 yrs) recommended flaring tool, is the Yellow Jacket, which I have, and the Ridgid. The YJ has a bale that gives the proper insertion depth for the flare. Not sure on the Ridgid. One thing on the YJ. I found that after a while I had trouble with slipping on the smaller tubes. Clean the inside of the clamping portion and you are good. Always cut off the flares on the line set, and make your own. Always carefully ream the inside of the tubing. BTW, I put in a dual system for my daughter and when I did the nitrogen purge I captured a small bit of copper shaving from the reaming and I was very careful with it. I would not have been happy with that in the system.

If you intend to use the heat side, get the unit off the ground or pad. In the defrost cycle, the unit reverses and melts the accumulated ice on the condensing unit. If the unit is sitting on a pad you may ice up the drain and in extreme situations ice build-up can modify that nice high efficiency fan in the condensing unit. Also, rain or run-off from the roof can splash dirt onto the face of the coil reducing air flow. I had a guy do this, putting the unit under and eve and after a heavy rain he got a service call for no op. I got the call and went out with him on this one week old install and the lower half of the coil face was completely packed with dirt. I also went out on a call where they wanted to hide the condensing unit. When I got there I walked around the corner and there behind the bushes were about a hundred garter snakes in and around the condensing unit. Kinda freaked me out. Minced snake. Get them off the ground.

Your line-sets come in specific lengths. Your unit may, depending upon line set length require additional refrigerant. Keep track of the length by measuring the remaining line set and be precise in the adding of 410A. Some manuf have minimum line set lengths. Do not get to close.

Mini-splits are terrific equipment, at least in my opinion. That said, if you want an invitation to your own personal Twilight Zone, cut a few steps out of the process or be shoddy in execution.

I am no longer in the rep business and no longer have an affiliation with any manuf. As a point of information for those considering a mshp there is a lot of good info out there. I just downloaded the '13 Fujitsu Brochure with all their specs. There is a lot of good info there. If you go there, pay attention to the minimum and maximum outputs and consider them in sizing. That can generate some good conversation

I have to go rough-in my new roof mounted 15 RLS for the new kitchen addition

 

[monkeyspanners]

I put two panasonics in, one inverter one fixed speed. Was pretty simple but its my day job

 

[nsblue]

Your line-sets come in specific lengths. Your unit may, depending upon line set length require additional refrigerant. Keep track of the length by measuring the remaining line set and be precise in the adding of 410A. Some manuf have minimum line set lengths. Do not get to close.

I am planning on a DIY install for a couple of Fujitsu RSL2 mini splits in the next couple of months. The installation manual dictates how much refrigerant to add if you go with longer line-sets but it doesn't say to remove refrigerant with shorter line-sets. It states that the charge is sufficient for up to 49'. Would there be any issues with a 15 or 25 foot line-set if I did not remove any refrigerant?

Thanks,

Dean

 

[unluckyty]

Just installed a Friedrich mini split 115v unit. Fully self installed, 25' line set plugs into 115v outlet inside. Works great, very happy so far.

Greg

 

[RKA]

I am planning on a DIY install for a couple of Fujitsu RSL2 mini splits in the next couple of months. The installation manual dictates how much refrigerant to add if you go with longer line-sets but it doesn't say to remove refrigerant with shorter line-sets. It states that the charge is sufficient for up to 49'. Would there be any issues with a 15 or 25 foot line-set if I did not remove any refrigerant?

Thanks,

Dean

I can't tell you why Fujitsu specs theirs different from the others, but you'll be fine following their recommendations. Read carefully for a minimum length. Mine spec'd min 16-17 ft and that's exactly what I used even though I didn't need that much. I didn't remove any charge from the system and its been working great.

 

[monkeyspanners]

What RKA said, plus be aware that really short pipe runs can lead to you being able to hear refrigerant whooshing through the evaporator.

 

[nsblue]

Thank you RKA and monkeyspanners, the minimum length I will use is 15' and I have read somewhere that over 12' and you should be fine with this particular mini split.

 

[mobiledynamics]

Interesting read. For short runs....where I suppose alot of one-off single unit installs are, where let's say they hang it right off the wall , what happens with the extra slack. Is it just *tucked* behind the compressor. Just curious...

 

[Jackfre]

I believe the reason Fujitsu has a minimum length is to accomodate the "pre-charge volume". There is a certain amount in the accumulator that gets fed inot the system, but in order to maximize the line set length that does not require additional refrigerant they need a bit of line set on them. These are so much simpler to install if you do not have to add 410A to the system. If you meet the minimums you do not need to worry about the pre-charge volume.

If you are to close to the evaporator and can't meet the minimum you should lay a serpentine (back and forth) pattern with the line set. Never leave the line set coiled as it will trap oil and well, you won't be happy. Never, is not negotiable here. Even laying the line set coiled horizontally is a problem as over time things sag and traps can be created. Serpentine!

 

[nsblue]

I'm sure that I read somewhere what the minimum length for the Fujitsu 12RLS2 and 15RLS2 I just can't find it now and it's not in any of the manuals that I have found. Jackfre, do you recall the minimum length required for these models?

 

[DB2]

FWIW - I called Mitsubishi HVAC a few weeks back to ask them this same question (their install manual just states "up to 25 ft - no additional refrigerant needed"), and the person I spoke with said there was no minimum length requirement for the pre-charged refrigerant.

That said, I was looking at another mini-split install manual (an off-brand, can't remember which), and it stated you had to evacuate charge for line sets less than 25 ft, using the "reverse" of the formula used to add charge for longer line sets.

 

[JakeKohl]

FWIW - I called Mitsubishi HVAC a few weeks back to ask them this same question (their install manual just states "up to 25 ft - no additional refrigerant needed"), and the person I spoke with said there was no minimum length requirement for the pre-charged refrigerant.

That said, I was looking at another mini-split install manual (an off-brand, can't remember which), and it stated you had to evacuate charge for line sets less than 25 ft, using the "reverse" of the formula used to add charge for longer line sets.

The LG units that I installed recommended that you remove refrigerant for linesets shorter than the specified amount (X amount per foot of lineset). I also helped a friend install an off-brand unit that was close coupled and the folks he bought his from had advised that mounting them to closely has ill effects with pulsations from the compressor reaching the indoor unit. I'm not sure if this was just a "noise" issue or if it affected the performance of it.

 

[RKA]

I'm sure that I read somewhere what the minimum length for the Fujitsu 12RLS2 and 15RLS2 I just can't find it now and it's not in any of the manuals that I have found. Jackfre, do you recall the minimum length required for these models?

Min length for the AOU12RLS2H (the model of the outdoor unit I believe is used on the 12RLS2 system) is spec'd at 10 ft. The only negative consequence they mention is sound transmission from the outdoor unit to the indoor unit, hence the need for that recommendation.

If you want the Installation manual, PM me with your email address. Note, Fujitsu writes separate installation manuals for the outdoor unit and the indoor units. I remembered this only after squinting my eyes for a few minutes looking at the manual for the indoor unit and wondering where all the info was about the outdoor unit!).

 

[mobiledynamics]

DB2 -

Just curious.....as the 3-5 calls I have put to Mitsubishi - they only took dealer direct phone calls...Not any end user.

Someone did speak with me in length, when I advised them I had a *issue* with my installing Platinum Dealer...

 

[DB2]

DB2 -

Just curious.....as the 3-5 calls I have put to Mitsubishi - they only took dealer direct phone calls...Not any end user.

Someone did speak with me in length, when I advised them I had a *issue* with my installing Platinum Dealer...

The number I called said press 1 for consumer or 2 if you are a dealer or facilities maintenance staff. Technically I am a facilities manager so I pressed 2, and no one asked for any credentials.

 

[gt390]

I have one in my garage a few years now, no big deal, lots of the other replies talk about flaring and such. I like the Imperial Eastman flaring tools, good industrial american made stuff, you can find a nice set on ebay for reasonable. Learning how to do flares also helps with brake lines (double flaring). I did install a disconnect, evacuated the lines, and also installed a sightglass. I ran the hoses and wires inside from the wall unit down, and out a piece of 2 inch PVC through the wall. The condensate is also a handy source of distilled water for batteries and antifreeze.
Alan

 

[Highbeam]

The condensate is also a handy source of distilled water for batteries and antifreeze.
Alan

Uh, no. The condensate is contaminated with nasty junk being blown on it before it drips into the nasty pan. You'd be better off using rain water from your gutters. The condensate effluent is not the same as distilled water from a distillery.

 

[R7237]

Did my own install, had a friend HVAC guy pull vacuum. Line sets were copper line that I bought and plastic drain hose. $900 for the LG two head 18000 BTU system, poured slab with bag concrete and made sure line sets were both 25' to ensure no additional coolant was required. Have worked great for two years now. Probably $1,100 in the whole setup, and asked the HVAC guy what it would cost if he bought it and installed, and was told he did an exact setup for $6k the week prior,,,, so guess I did ok.

 

[sands35]

Uh, no. The condensate is contaminated with nasty junk being blown on it before it drips into the nasty pan. You'd be better off using rain water from your gutters. The condensate effluent is not the same as distilled water from a distillery.

Yeah - more than a few cases of Legionnaires disease from AC condensate.

 

[sands35]

Anyone have any recommendations for self install units? (not going to touch LG or Samsung - they are competitors to the company I work for)

 

[RKA]

Self install vs. what? I'm not clear what you're asking.

 

[Falcon67]

I just read over the Fujitsu one to many deal on their web site. I like the cassette and the slim duct deals especially. The 8 way system would be a good way to piece meal cut over from a traditional HVAC ducted system. The problem I see for a house is sizing and controlling - say two 120~150 sq/ft bedrooms with a 100 sq/ft bath across the hall. Slim duct all those? 9K cassettes in the rooms and slim the bath off the living room? Etc. Hard to visualize a house install in a traditional partial open, boxed off room type building.

 

[sands35]

Self install vs. what? I'm not clear what you're asking.

recomendations for brands that are easy to diy install.... (really not a complicated question....)

 

[nsblue]

Has anyone had any experience with the Senville Aura line of mini splits? I am still going with Fujitsu for my garage but I am curious about these units as the specifications look good and the price is right. They have warehouses in both the US and Canada and they don't discourage DIY installations according to their website.

http://senville.com/aura-series/