MRCOOL DIY Mini Split, Seriously, I Think...

[EricVonHa]

Finally took the plunge. Rebates tough to pass up. Fed is like $300 and local PECO is $200-ish. Home Depot is nice enough to list these right on the product page. SOLD!

Bought an 18k DIY and the install went great. Unit works great. WiFi app-- not good, no connection to the router

I have an old Fios router that is only B & G bands. My guess is that the Mr Cool AP is "N" because the Mr Cool unit never shows up in my Router table of connected devices (yeap, after resetting power to the mini-split and so forth)

My phone connects directly to the mini-split AP no problem (phone direct to the mini-split)

The issue is getting the mini-split to connect to the router.

I can't find any WiFi specs on the Mr Cool WiFi portion. Any techno-geeks know anything?

Turned out to be a password incompatibility issue with the old Fios router. Odd, very odd. There are a number of wireless devices that authenticate to the router just fine, just not the "smart" MRCOOL wifi dongle.

I connected it to another router and the password took no problem.

Remote control HVAC from anywhere now!

 

[gtae07]

My MrCool is 4 years old and had developed a leak on the inside coil. HVAC guy put nitrogen in and we head it squealing in the indoor unit. Contacted Ingrams and they are getting a replacement indoor unit ready to ship, no hassle. MrCool's warranty is real and Ingram's is a pleasure to work with.

Hopefully it comes in soon as my shop is my temporary home office and it's starting to get warm outside...

 

[Malaworkerbee]

My MRCOOL DIY 12k 22 SEER unit came in yesterday. Going to install it in the office. The space is only 11'x10', and every calculator tells me I only need a 9k btu unit. But I overspec'd slightly as it's the hottest room in the house and there are two high end computers adding to the heat load. Price difference was $50.

Also bought a Yellowjacket open ended torque wrench ($150). Might as well do it right. Still waiting on the wall bracket and I still need to buy a lineset cover. Still haven't figured out power. My panel is on the opposite side of the house. I can't run romex through the attic as the duct work up there prevent me from crossing to the other side.

My buddy is a contractor and will help me with wiring to code once he's available. We might just run conduit along the outside of my house, either through the soffits or near the ground.

Already have a AC disconnect with 15amp fuses ready to go. For the time being I plan on running the unit off a 10/3 extension cord.

My house is stucco so drilling that 3.5" hole is going to be fun. Lastly my office is above the garage, and the space between the garage and 2nd floor is not insulated..... so I'm going to have to blow in insulation soon. Fun times

 

[justinjoyal]

2.5in is enough hole to get everything through.

 

[Malaworkerbee]

Maybe so but the unit comes with a 3.5" through hole bushing and I used it. It wasn't hard. Diablo hole saw (Already had) attached to a Bosch SDS Bulldog impact hammer. Took only a few minutes to cut through all the metal mesh in the stucco.

I've drilled similar holes before with my Milwaukee drill and even though it was more powerful it took a lot more work.

 

[nadogail]

After comparing the costs of several contractors and units, I gladly paid up for several reasons.
1. Local Installers reputation for customer service.
2. Reputation of the manufacturer.
3. If the job somehow went sour, I had someone who had a reputation to defend and pockets deep enough to take responsibility and correct any problems.
4. I can stand back and say "It's not my fault, they did it"

 

[nealric]

Question on the Advantage vs DIY units: are they really identical other than the pre-charged line set?

Seems like the cost differential is around $400 for the 18k unit. That's a LOT if the only difference is the lineset. I've heard $200-300 quoted for an HVAC guy to verify the install, pull a vacuum, and start it up. Any real reason to buy the DIY if I can get someone to do it for that?

 

[Malaworkerbee]

Question on the Advantage vs DIY units: are they really identical other than the pre-charged line set?

Seems like the cost differential is around $400 for the 18k unit. That's a LOT if the only difference is the lineset. I've heard $200-300 quoted for an HVAC guy to verify the install, pull a vacuum, and start it up. Any real reason to buy the DIY if I can get someone to do it for that?

If you can really get a certified HVAC guy to install it, pull a vacuum and verify it works for that then yes it's worth it. Doesn't have to be Mr Cool. Mirage, Pioneer, Bunch of others are all much cheaper without the precharge lineset.

For the price of the DIY unit you can get a entry level Daikin, Fujitsu or Mitsubishi units which are regarded as the best.

Locally I can't get anyone to do it for less than around $2k. So self install it is.

Also, the pre-charge lineset isn't cheap. If you wanted to buy a longer set or you messed up and wanted a replacement (Only viable if you haven't already opened the lines on the cassette) then that alone will be $200-300.

My unit is now installed and I will say it is amazing. Here in Vegas we are expecting 100F temps this week. Even setting it to 85 on low it's keeping my office cold. It's been keeping me so cold that I've had to wear a long sleeve shirt. Still playing with the temps/settings. It's nice being able to turn the house AC off.

 

[jjrbus]

I do not know about the rest of the country but finding a knowledgeable AC tech is not as easy as picking up the phone.

The last straw for me was a tech that showed up in a fancy wrapped van with a Harbor freight vacuum pump, a old leaking manifold set and no flaring tool! That is at $95 hour!

There are good techs out there but they are busy and not easy to find!

Only my opinion and worth what you are paying for it.

 

[nealric]

If you can really get a certified HVAC guy to install it, pull a vacuum and verify it works for that then yes it's worth it. Doesn't have to be Mr Cool. Mirage, Pioneer, Bunch of others are all much cheaper without the precharge lineset.

I wouldn't expect an install for that. Literally all they'd do is pull a vacuum and verify its not leaking.

 

[Browneye]

My MRCOOL DIY 12k 22 SEER unit came in yesterday. Going to install it in the office. The space is only 11'x10', and every calculator tells me I only need a 9k btu unit. But I overspec'd slightly as it's the hottest room in the house and there are two high end computers adding to the heat load. Price difference was $50.

Also bought a Yellowjacket open ended torque wrench ($150). Might as well do it right. Still waiting on the wall bracket and I still need to buy a lineset cover. Still haven't figured out power. My panel is on the opposite side of the house. I can't run romex through the attic as the duct work up there prevent me from crossing to the other side.

My buddy is a contractor and will help me with wiring to code once he's available. We might just run conduit along the outside of my house, either through the soffits or near the ground.

Already have a AC disconnect with 15amp fuses ready to go. For the time being I plan on running the unit off a 10/3 extension cord.

My house is stucco so drilling that 3.5" hole is going to be fun. Lastly my office is above the garage, and the space between the garage and 2nd floor is not insulated..... so I'm going to have to blow in insulation soon. Fun times

The air handler comes with a wall bracket - was it missing?

You might see what else is on a nearby outlet circuit - although it is supposed to have a dedicated circuit I ran mine off a little used existing one. This is not installation or electrical advice - just what I did on mine. IIRC peak pull is about 9amps. I did use an external power disconnect.

Same boat on size - the 12k was the smallest size at the time - it's ice cold. LOL

The harbor freight carbine hole saw cuts through stucco like butter. Also comes with a file to hog out the hole to the size of the sleeve.

You may even be able to throw some batts up in the crawl space over your office.

I used plastic rain gutter for a line cover - $9:



And painted it...

 

[Malaworkerbee]

The air handler comes with a wall bracket - was it missing?

You might see what else is on a nearby outlet circuit - although it is supposed to have a dedicated circuit I ran mine off a little used existing one. This is not installation or electrical advice - just what I did on mine. IIRC peak pull is about 9amps. I did use an external power disconnect.

I'm wall mounting the outside unit. The bracket for that came in today. Still waiting on lineset covers but the unit is up and running, just on a box......

I could pull power from the other side of the wall but it's not really smart to do so. The lines going there are shared with all of my living room outlets and lighting.

My best bet is to run new lines through the garage's ceiling. It's an open space and easy to pull wire through. The issue is what happens once I get out of the garage. I have a spanish tile covered walkway and an HOA to deal with so whatever I do has to be clean/hidden.

My office is above the garage on the left side of the attached image.

 

[Browneye]

Fire-stops in studwalls make for fishing wire a PITA.

 

[clymer]

Guys: I have a question / looking for feedback. I built a lake house in NH. The 2nd floor bed rooms are cathedral ceiling with rafters sitting on 4' knee wall. I had originally planned to go with attic mounted head unit, ducted, with ducted vents into each br and return from the hallway. Mrcool now has a multi-head, single condenser unit, where I could put a wall mount (12k) for the down stairs and wall mount (9k) for two of the br's up stairs. Looking at this because I have gotten two quotes so far, one for 15K if I do all of the ducting pre-work and one for 22K. This mr cool multi-head diy unit totals at 3500 before tax, with the three heads. That being said, the 25' of pre-charged line means that I would have to mount one of the br heads against the knee wall. If the head unit is only about 20" off the floor, would I expect to see any cooling benefit? (yes, I realize it's a dumb question, but looking to see if anyone has actually tried this. The br's are small, but ceilings pretty high. It's just a lake house, not expecting miracles, and I imagine for heating that this would be OK closer to the floor, but cooling is the goal as this is only a summer place.. see image / feedback appreciated.

 

[SALIV8]

I’m not sure if Mr cool has the floor mount but the floor mount would probably work best regarding that sketch if they offer one.

Would your scenario work? Probably but it is against manufacturers directions I would presume. My heads needed to be at least 5 or 6’ off the ground. I don’t think it will give good air movement so close to the floor.

I would ask mr cool and see what they say.

 

[clymer]

..Yeah, the sales rep on ingrams chat said it's a non-starter. I have seen posts on-line where people place these 18" off the floor for heating (makes sense, heat rises), but I need it to **** heat out of the place. I will measure some stuff tomorrow when I head up there and see where 25' from the pad I poured ends up, but I might end up giving this a go.. I have been using an indoor AC (vent out the window) for this same bedroom and it works pretty well, not sure how a 9k btu head unit from a 30k btu condenser would do any worse; the elevation of the vent is about the same.. The place is insulated well (closed cell spray in the rafter bays, 2.6" polyiso cut/cobbled in the stud bays)

Just thinking of the numbers: saving 12K+- sounds like a no-brainer even if placement isn't optimal and I have had great luck with the one I have so far. My job situation took a precarious turn with this covid-****

 

[nealric]

Bumping this thread again for another question...

It looks like the delta between the 24k Mr. Cool Advantage and DIY is $500. However, Ingrams sells a precharged lineset for $250, which is also nicer because it is shorter, so no need for a giant coil.

Any reason why I couldn't just buy the Advantage + the lineset instead of the DIY? I realize you lose the warranty if you self install, but is that it?

 

[Fueler]

..Yeah, the sales rep on ingrams chat said it's a non-starter. I have seen posts on-line where people place these 18" off the floor for heating (makes sense, heat rises), but I need it to **** heat out of the place. I will measure some stuff tomorrow when I head up there and see where 25' from the pad I poured ends up, but I might end up giving this a go.. I have been using an indoor AC (vent out the window) for this same bedroom and it works pretty well, not sure how a 9k btu head unit from a 30k btu condenser would do any worse; the elevation of the vent is about the same.. The place is insulated well (closed cell spray in the rafter bays, 2.6" polyiso cut/cobbled in the stud bays)

Just thinking of the numbers: saving 12K+- sounds like a no-brainer even if placement isn't optimal and I have had great luck with the one I have so far. My job situation took a precarious turn with this covid-****

Here is a thought.
To get the inside unit up where it needs to be why not build an extension housing away from the slanted ceiling. I think you could do that and nicely box in the lines leading down to the straight wall.

 

[Fueler]

Bumping this thread again for another question...

It looks like the delta between the 24k Mr. Cool Advantage and DIY is $500. However, Ingrams sells a precharged lineset for $250, which is also nicer because it is shorter, so no need for a giant coil.

Any reason why I couldn't just buy the Advantage + the lineset instead of the DIY? I realize you lose the warranty if you self install, but is that it?

I am in the need for another unit and have been wondering the same thing.

 

[Browneye]

Yes, you may have issue with warranty coverage on a non-DIY unit. The disclaimer in the warranty text is very clear about having proof of qualified installer.

Additionally, I'm not sure the lineset connections on the Advantage unit are the same on the DIY. For the latter, the lineset comes already connected to the air handler (indoor) part.

For handy DIY'rs, Ingrams also has some 'scratch-n-dent' units at substantial discount. My second unit was one of these, saved a ton of dough and it works perfectly.

 

[nealric]

Yes, you may have issue with warranty coverage on a non-DIY unit. The disclaimer in the warranty text is very clear about having proof of qualified installer.

Additionally, I'm not sure the lineset connections on the Advantage unit are the same on the DIY. For the latter, the lineset comes already connected to the air handler (indoor) part.

For handy DIY'rs, Ingrams also has some 'scratch-n-dent' units at substantial discount. My second unit was one of these, saved a ton of dough and it works perfectly.

Yes, but I'm not sure the warranty is really worth $250 to me. No scratch and dents around at the moment.

 

[nealric]

Yes, but I'm not sure the warranty is really worth $250 to me. No scratch and dents around at the moment.

For what it's worth, after inquiring, Ingrahm's says that the pre-charged linesets do not work with the Advantage units. I'm not 100% sure that's strictly correct, but it's clear that they won't support you if you go that route.

 

[Browneye]

Yes, but I'm not sure the warranty is really worth $250 to me. No scratch and dents around at the moment.

You'll spend twice that getting a tech to show up for ANYTHING HVAC related. I guarantee it.

Scratch and dent? Sure there are, they're here: https://iwae.com/outlet/heating-air-conditioning-outlet/

If you don't need or want a DIY unit, and you either 'have a guy' or the tools to do a vac, test, and turn up, then there are plenty of other options and plenty of other brands to choose from. Some are a LOT less. Mr. Cool doesn't have a lock on mini-splits for the US market.

And if you have a guy that will sign off on turn-up as the installer to validate a warranty certificate, they can assist you with any subsequent warranty claims. Just be sure to confirm that before proceeding.

I was going to buy a vacuum pump and gauge set and just do my own - it's not that hard. But the warranty claim hassle and risk wasn't worth the little bit of premium cost and ready to go nature of the DIY units. So I bought two of them a year ago and they're just fantastic. Total cost was about $2500 all in for both of them. It's a game-changer for the old house.

I was also able to find a couple of 'ac guys' that would do a final - vac, test, and turn up - for about $400. I just find these types to be less than reliable, it's a sketchy business unless it's a fifteen thousand dollar project. One purveyor said they have one package 'for homes like ours' and that was a complete central system change out, starting at fourteen thousand. "Take it or leave it, we don't care." Yeah, GTFO dood.

 

[nealric]

You'll spend twice that getting a tech to show up for ANYTHING HVAC related. I guarantee it.

Scratch and dent? Sure there are, they're here: https://iwae.com/outlet/heating-air-conditioning-outlet/

If you don't need or want a DIY unit, and you either 'have a guy' or the tools to do a vac, test, and turn up, then there are plenty of other options and plenty of other brands to choose from. Some are a LOT less. Mr. Cool doesn't have a lock on mini-splits for the US market.

And if you have a guy that will sign off on turn-up as the installer to validate a warranty certificate, they can assist you with any subsequent warranty claims. Just be sure to confirm that before proceeding.

I was going to buy a vacuum pump and gauge set and just do my own - it's not that hard. But the warranty claim hassle and risk wasn't worth the little bit of premium cost and ready to go nature of the DIY units. So I bought two of them a year ago and they're just fantastic. Total cost was about $2500 all in for both of them. It's a game-changer for the old house.

I was also able to find a couple of 'ac guys' that would do a final - vac, test, and turn up - for about $400. I just find these types to be less than reliable, it's a sketchy business unless it's a fifteen thousand dollar project. One purveyor said they have one package 'for homes like ours' and that was a complete central system change out, starting at fourteen thousand. "Take it or leave it, we don't care." Yeah, GTFO dood.

Ended up just ordering a 24k advantage. No scratch and dent in that size. Went for them over the pioneer due to the Alexa/wifi support. A friend of mine got his mini split done (just evac and test) for around $200, so I’m quite sure I can find someone for less than $500. May be a regional thing. If I can’t find anybody, I will just buy a vacuum pump and gauges and DIY.

 

[Ilikeike]

Ended up just ordering a 24k advantage. No scratch and dent in that size. Went for them over the pioneer due to the Alexa/wifi support. A friend of mine got his mini split done (just evac and test) for around $200, so I’m quite sure I can find someone for less than $500. May be a regional thing. If I can’t find anybody, I will just buy a vacuum pump and gauges and DIY.

You can find a guy cheap in between seasons, and during the whole Covid thing many were laid off. Now its getting hot, hard to find a side job guy.

 

[akpingel]

Just picked up a 36k unit. Couple things are odd. Ingrams says it needs an 8/3 wire but looks like you only need 8/2. Bought their pigtail and it is too large to mount to the condenser through the prepunched holes. What gives?

Anyone wall mount a 36k condenser on cinder block?

Sent from my SM-N970U using Tapatalk

 

[akpingel]

Just picked up a 36k unit. Couple things are odd. Ingrams says it needs an 8/3 wire but looks like you only need 8/2. Bought their pigtail and it is too large to mount to the condenser through the prepunched holes. What gives?

Anyone wall mount a 36k condenser on cinder block?

Sent from my SM-N970U using Tapatalk

Mounted and installed. Currently running and a few things to tidy up like putting the wall back together and running a line cover. Can't believe how quiet the condenser is. I'll check in here in the summer when it gets stupid hot out. Currently my shop is only insulated in the walls so I'm running an experiment for all those out there like me!

Sent from my SM-N970U using Tapatalk

 

[shade]

Its stupid hot here. I think 110 today.
My 2 Mr Cool units kick ***.
Quiet, efficient and cool the garage no issues

 

[ItsJustJoe]

I built a box that sits out from the wall for the unit to mount to. That allowed the line set to run up inside the box to the attic. It is looped in one big loop and drops down through the soffit to the outside unit.

I just ordered the 24k unit from Costco for $1499. I plan on doing what ncboat described. How tight can the lines coming directly out of the back of the interior unit be turned? Do they have the same anti-kink cable wrapping the lines themselves have?

 

[Fasthotrod]

For what it's worth, after inquiring, Ingrahm's says that the pre-charged linesets do not work with the Advantage units. I'm not 100% sure that's strictly correct, but it's clear that they won't support you if you go that route.

It's absolutely correct. The Advantage series uses your typical flared fittings on the condenser, evaporator, and line sets. Page 25 of the installation manual shows the connections:

https://mrcool.com/wp-content/dox_repo/mc-adv-3-im-en-01.pdf

Compare that to the DIY and you will see that the connections are nowhere close to being compatible. Page 21 of the installation manual:

https://mrcool.com/wp-content/dox_repo/mc-diy-3-es-im-um-en-01.pdf

Hope this helps.

Mark

 

[yeldogt]

Don't confuse "DIY" ..... Not all Mr Cool are the "DIY" line of mini's.

Mr. Cool recently came out with the third generation "DIY" .... It has the quick connect fitting on both the indoor head and outdoor compressor. The previous generation had only the connection for the outside unit -- the line set came preinstalled on the inside head. This was a pain to work with.

This new Generation allows for different line lengths and I'm sure an ever expanding model range.

Unfortunate -- even this new Gen 3 -- is not a "hyper heat" .... so the cold performance will not match others they sell

 

[fwillison]

I have had problems with mold growing (caking really) on the blower fan of my mini split.
I had it serviced and cleaned, but it was done poorly. Most but not all the mold was removed. I had them install a Fresh Aire UV LED to prevent recurrence, but does not seem to be doing the job (only 1.5 wks so far, but seems like mold may be coming back).
I live in Tulsa, OK with moderately high humidity, but my clay soil holds moisture and it seems is a breeding ground for mold.
Seems like a pretty common issue - anyone else with experience on this problem?

 

[Browneye]

I just ordered the 24k unit from Costco for $1499. I plan on doing what ncboat described. How tight can the lines coming directly out of the back of the interior unit be turned? Do they have the same anti-kink cable wrapping the lines themselves have?

There is a more or less a rigid length of pipe (couple feet?) that connects to the back of the unit, and it quite difficult to bend. My assumption is to prevent kinking the line. It also swivels so as to exit the opposite side of the head unit, so that may be a possibility for you. The lineset simply doesn't make sharp bends, maybe about a 12" radius at most.

 

[Choi0706]

Is the air handler supposed to sit flush against the wall? Mine is sticking off a bit. Especially the side with the hoses to run through.

 

[SALIV8]

Yes it should sit flush. Double check you have bottom clips inside the plastic and you can have someone gently pull the outside line set while you push it into place.

 

[Git]

I have had problems with mold growing (caking really) on the blower fan of my mini split.
I had it serviced and cleaned, but it was done poorly. Most but not all the mold was removed. I had them install a Fresh Aire UV LED to prevent recurrence, but does not seem to be doing the job (only 1.5 wks so far, but seems like mold may be coming back).
I live in Tulsa, OK with moderately high humidity, but my clay soil holds moisture and it seems is a breeding ground for mold.
Seems like a pretty common issue - anyone else with experience on this problem?

I have to pull the blower fan out every year to give it a good cleaning on my Mr Slim and I am in S Cal

 

[Choi0706]

does the air handler supposed to cover the hole?

 

[akpingel]

Yes it should cover the hole. Are you using the template?

 

[Browneye]

 

[jjrbus]

I have had problems with mold growing (caking really) on the blower fan of my mini split.
I had it serviced and cleaned, but it was done poorly. Most but not all the mold was removed. I had them install a Fresh Aire UV LED to prevent recurrence, but does not seem to be doing the job (only 1.5 wks so far, but seems like mold may be coming back).
I live in Tulsa, OK with moderately high humidity, but my clay soil holds moisture and it seems is a breeding ground for mold.
Seems like a pretty common issue - anyone else with experience on this problem?

The first mini I installed quickly had a mold issue, less than a year. I am in FL and mold is a constant problem. But this stuff was hell to get off, It must have been some weird mold from China. I had to remove the blower wheel and use straight bleach to remove the mold. It has grown mold again, but the normal FL mold which is not as hard to remove and reacts to available cleaners.

I was given all kinds of advice, turn AC off and let fan run to dry out unit, drain pan must not be draining, install a whole house humidifier, have house tested for mold etc.

Here is what I found after hours on the net and my opinion. There is absolutely no mold on the coils, none, nada, zip! There is no mold in the drain pan. The only mold in the drain pan and the case is what is slung off by the blower wheel.

My conclusion and opinion, the &^%$# blower wheel plastic is porous allowing the mold to get a foot hold and grow. Nothing else makes sense. It seems that about 2% of minis have this issue, usually in humid areas.

The design of the mini for cleaning is unconscionable, I would imagine there will be a class action suit someday.

I have yet to see any documentation that any UV lights work in minis, much fancy advertising and hype, but no documentation. I am trying to get info on which plastics are used as some plastics are damaged by UV light.