Mini-split A/C Shopping...

[rickairmedic]

Same here but I still found it funny.


Rick

 

[mpire]

Ok, so I took a picture of the A/C intake for you to laugh at.

Apparently I have trouble getting enough air over my coils.

 

[rickairmedic]

Yep standard builder grade stuff there . The sad part is the opening at your air handler is probably closer to the size of the filter than the size of that flex duct.


Rick

 

[mpire]

So would there be any benefit to ripping it out and building a box out of blue foam like I had mentioned before?

There is something pushing in on the duct that is messing up my airflow.

Gotta love builder grade!

 

[rickairmedic]

I think I would first figure out what is pushing in on the duct there since it will still be there even if you change out the duct. Then figure out if you can remove whatever it is without causing the house to fall down .

Rick

 

[mpire]

The short answer is no since that is holding up the A/C unit.

Its part of the structure.

So lets think of alternatives.

 

[rickairmedic]

Where the flex is pushed in on the left of the picture it cant be supporting the AC unit as it looks bowed in at least 6" or more down from the unit . I will say if it is supporting it it isnt doing a very good job of it .Looks from here like the flex runs to the right and straight up from the filter rack. I would say if thats the case you should be able to pull it out of there ( if you can get to it from the other side where the unit is located ) . Then simply box in the return with Ductboard using the wall as your 4th side of the box. I am not saying this is the right way to do it just the easy way for you to do it and have it work and flow better than the mess thats there now. Have I ever mentioned I hate Flex Duct .

Rick

 

[mpire]

Ok, so why can't I get away with using the foam board instead of that messy duct board?

 

[rickairmedic]

Cause its not the right stuff to use . Foam board is for insulation not for ductwork. Really ductboard isnt that bad . Regular batts of insulation are much worse as far as getting covered with fiberglass. Remember it always costs more to do it twice than it does to do it once ( the right way ) .


Rick

 

[rickairmedic]

Make cardboard templates of your pieces then go out to the garage or outside and cut the ductboard to size then go in and put it in .


Rick

 

[mpire]

Before I undertake this project, is there any chance that opening it up and making the box out of duct board will REDUCE the amount of air flowing over the coil?

 

[rickairmedic]

Nope unless you do something really wrong you wont reduce the airflow anymore than that flex already is . I would guess from what I can see that you will end up with a basic box behind the wall the filter rack is on that goes up to the bottom of the air handler.

Rick

 

[stevefasano]

removed due to

 

[mpire]

Ok, back on topic....

Its been a while, and I have been traveling and then sick, and lots of other excuses.

I got the power wire run, and the line-set cover installed on the side of the house yesterday.

So now I am to the point where I need to install the hard lines.

One of the flares appears to be damaged. So now I am trying to figure out how to repair it. I picked up a flare tool, and a de-burring tool for doing copper pipe. Is there a secret trick to this, or do I just cut, de-burr, and then flare?

I am thinking I can just cut off excess copper, re-flare, and then connect it to the outside unit. If I have to do one anyway, whats the difference?

Once I get that part figured out, I can do the final install on the inside unit after I attach the hard lines.

Then I have to finish:

1) Mount Outside unit.
2) Install Outside power box & conduit to unit.
3) Attach hard lines to outside unit.
4) Vacuum & set refrigerant levels
5) Re-landscape the area to make HOA happy.

The house is being painted today, so I might as well wait until they finish before I finish the outside unit.

 

[mpire]

BTW, any reason I shouldn't use this great stuff to fill the gaps inside the walls? I had to cut a hole in the wall to fish the power wire down to the opening for the line-set cover. I cut about a 2 inch hole in the drywall. Now it seems sealed in every way, but I could feel the air blowing in my face while I was running the wire. I am not sure how the air is getting through there, because it was a bear to get the wire run.

Someone told me it attracted termites, so I am not sure what to believe sometimes.

Here is the hole in the wall with the insert that came with the a/c unit.

 

[mpire]

Here is a picture of the line-set cover.

Its definitely too big for the stuff going inside it, but I guess it can't hurt. Its too much trouble to try and find a replacement at this point.

Far away shot:

Here is a close up on the bottom half. You can see the side of the house that goes from concrete block stucco to stucco on plywood. It bows out right at the bottom a little. Not sure why, but I assume its part of the construction. The stucco is about 3/4 to 1 inch thick on top of lath.

Anyways, any ideas on how to make the transition better other than adding spacers or something? The top half seems fine, but that gap in the middle probably isn't a good thing.

 

[Jackfre]

I never use the factory flare on a line set. If you have a good flaring tool, cut, de-burr cleanly and flare you will be better off. That foam will work. Perhaps you should look at putting a piece of 1x4 ( or appropriate dimension) as a base for the first story section of the line set cover to build it out to match the set of the second floor. It paints out real well.

 

[Jackfre]

Oh, I forgot to say that your job is really easy from here Glad you are felling better

 

[mpire]

I never use the factory flare on a line set. If you have a good flaring tool, cut, de-burr cleanly and flare you will be better off. That foam will work.

I have a flaring tool, not sure if its good or not.

What I don't really get its the de-burring part. I seem to be just making it worse.

Good idea on the 1x4. Tired people have trouble putting together obvious solutions. I will have to through the table saw and cut it down so its a smooth transition.

 

[Jackfre]

I have a good multi-flute countersink I use for de-burring. It only requires a twist and you cut the burr off the inside. I do it by hand as I also run that bit in the dp and power drills.

 

[mpire]

Well, I picked up some stuff made by brasscraft and I have my good old pipe cutter.

Think these will do the job?

 

[stevefasano]

removed due to

 

[mpire]

Ok, dumb question to follow...

Whats a double flare tool and do you have recommendations?

Ok, now I know what it is. Now to find one locally.

 

[rickairmedic]

Mpire you dont need a double flare on that lineset. There is no need for it there were thousands of systems running for " years " with single flares in this country and they didnt leak until they got old and the actual coils started leaking ( the flared linesets were still holding fine ) . Way back in the " good old days " The entire system was precharged including the lineset . When you connected everything it broke seals in the system and there was no need for a vacuum or anything then .


Rick

 

[mpire]

Thanks Rick. I am paranoid I guess.

I have to foam the holes and hang the outside brackets, move the shrubs, and then figure out where I am mounting the outside disconnect electrical box before I will even begin to worry about the line-set.

And now I am waiting on the HOA to approve the new LED outdoor lights before I can put lights back on the house. Seems funny to me. I broke the ones that were hanging on the house while taking them off. I wonder if I should hook up a motion sensor to the lights so it lights up when someone enters the driveway. Oh well, a project for another day!

At least the house is painted!

 

[brewchief]

You may be able to borrow a double flare tool from a local autozone or similar auto parts store, brakes lines are normally double flared, just make sure it will do the sizes you have.

I've only done a dozen or so mini splits over the years but I always double flare and have had no leaks that I know of.

I don't bother deburring when I double flare copper most of the time, as long as the cut is clean I seem to get a very nice flare.

 

[mpire]

So anyways.... I cleared away the bushes from where I was going to mount the compressor unit. Got the brackets out and starting measuring where to hang them on the wall.

Well, I have the smallest Mini-split unit available, and the instructions clearly say 11.8 inches from the back of the unit to the wall. The brackets they sold me only give me about 7 inches of clearance.

So this means I won't be using these brackets, and odds are I won't be mounting this on the wall either. That *****, I thought that would have been a nice setup. So now I find myself trying to decide how to set this thing up if I am not using the brackets.

Should I just stick it on a couple of 20" pavers and call it done?

Does it hurt to just set it on the ground? Shouldn't I bolt it down to something?

So back to square one, and don't buy air conditioner brackets from ACWholesalers.

 

[Jackfre]

Surprising that it is that much. I would call tech service and push the issue. Fujitsu is a 4" min to the wall. I think you can get 10-12" with the adjustment on the bracket. Correct?

You can certainly ground mount and use riser blocks to get 6-12" off the ground. You want to put the pad on a firm base. The trouble I have with condenser pads up my way is that the pads have a very small footprint and within two winters the frost heaves the unit way out of level, and that does, over the long term, affect the operation of the unit. You, I don't think, have to worry about frost heave. Btw, they do make condenser pads sized for ms'.

 

[mpire]

Well, I don't have frost down here, so that shouldn't be an issue.

However, I would think that mounting it up on the wall would be better for the unit.

I guess I have to wait till Monday and call then. Damn.

 

[Jackfre]

I think I'd choose to put it on the bracket at max extension...if you have good open air circulation around the unit. Keep in mind, most of these units are set directly on a pad, which eliminates air flow from below. You will be increasing circulation by suspending the unit. Oh, and do it today or tomorrow

 

[mpire]

Sorry to say I haven't accomplished very much today.

I did get one paver installed and I relocated some grass and a few other things.

Since I can't use the wall brackets as originally planned, I have to come up with a different way to mount the compressor. So what I have laying around are some 20" square pavers and some 4x4 posts. Not exactly as eloquent in execution, but it should get the job done.

I removed the grass and relocated it because good grass is a horrible thing to waste.

Then I built a small planter out of the 4x4 posts. The first row were set onto the ground and then leveled out. I used some wood stakes to hold it in place till I was happy and it was level. Then I screwed everything together. There are two layers of 4x4s, not sure if you can see it in the picture. Then I used some 24" rebar and rammed it through the 4x4s into the ground. Thats gives the posts a good bite into the ground so they don't go moving all around on me. Seems to work pretty well to keep things put.

Anyways, so then I filled it with some lava rock I had laying around. Looking back this isn't the best choice for leveling it out. I am thinking that I will have to go get some pea gravel tomorrow morning from the hardware store and try again.

I am debating if I should just pour a concrete pad to set the a/c on. I am not sure what I want to do.

Anyways, on top of the gravel will be the 20" pavers. The 4x4 posts keep them from wandering around. You can see one that I broke on the right of the planters. I stuck the a/c box on top of the gravel just to get an idea of the dimensions.

I still need to figure out how to bolt the compressor down though. Maybe i will use the anchors that came with the wall brackets. I have to think of something.

Anyways, should I just use the pavers and gravel, or should I get some quick setting concrete and just make it a solid pad?

 

[rickairmedic]

Well if you pour 3" of concrete into it then you can drill into the concrete and install anchors that way .


Rick

 

[mpire]

If its a 40x22x4 how many 50lb bags of concrete is that?

 

[AlbertaGuy]

I'm an HVAC mechanic in Canada and was curious when i saw this thread as I have been installing more and more LG splits lately, actually just finished another course last week. You seem pretty determined with all this. Never like to see homeowners playing with high pressure systems tho. The new refrigerants are way different than the old and theres too much potential that this job could cost you more in the long run if it gets botched somewhere along the way. You don't seem as comfortable with the wiring thing as you should. Are you required to take out permits in your area when you do installs to have things like the electrical inspected when you are done? Might be an idea cause if there was ever a situation its too easy for your insurance company to point to it as owner installed and voids your insurance. Just saying ...

 

[Rosco]

This is what I have for mine. Clean, sturdy, and the unit will bolt right on.

http://www.goductless.com/UV-Resistant-Plastic-Outdoor-Condensing-Unit-Pad-p/11099.htm

 

[mpire]

I'm an HVAC mechanic in Canada and was curious when i saw this thread as I have been installing more and more LG splits lately, actually just finished another course last week. You seem pretty determined with all this. Never like to see homeowners playing with high pressure systems tho. The new refrigerants are way different than the old and theres too much potential that this job could cost you more in the long run if it gets botched somewhere along the way. You don't seem as comfortable with the wiring thing as you should. Are you required to take out permits in your area when you do installs to have things like the electrical inspected when you are done? Might be an idea cause if there was ever a situation its too easy for your insurance company to point to it as owner installed and voids your insurance. Just saying ...

Running electrical wire and building a pad to put the outside unit on are jobs a monkey could do. I can read the directions as well as any monkey. However, I still plan on having the purge and charge settings done by my A/C guy. I will have to pay him, and that should satisfy the warranty requirements.

I just don't see much point in paying A/C service hourly rates to do things that I can do better and with more detail.

Also, if there is just one person doing things, it takes longer to get them done, and I have lots of other projects that are overlapping.

 

[mpire]

Ok, so the pad is done for now.

I ended up excavating the pad and pulling out all the lava rock and a good 4-6 inches of top soil. Then I filled it up with pea gravel. Then I put some sand on top to level it out to make sure it was perfectly level. Then I did the form work and poured the cement. Its quick setting, but I figure it doesn't have to be all that strong to do the job. Then I filled in the gaps with some leveling sand so I hope the sand sticks to the top of the concrete on the low areas and makes it look more aesthetically pleasing. There is a trough in the middle of the pad to allow the unit to drain and to keep any condensate from pooling under the unit. I am not sure why it has a drain, but it definitely has a drain pan and a drain connection for the outside unit. Go figure.

This should elevate the unit a few inches above the grass to keep it dry in even the heaviest rain. Plus I plan on drilling and bolting the unit down to the two feet.

It is perfectly level front to back, side to side, and diagonally. So that should be good enough for the 3/4 ton unit I am going to be using.

I seem to do things overkill. At least I will be happy with the results.

 

[mpire]

Well, does anyone know if they make brackets to space the outside unit a foot off the wall? The company I bought it from says that they are fine to use even though they hold the unit only 7 inches from the wall.

Anyone want to chime in? Should I go with the directions for 11.8 inches, or should I go with what the guy on the phone says and be ok with 7?

 

[terabyte]

hey mpire where in Florida are you?

 

[mpire]

Orlando.