someone set me straight please.

[chrrristopher]

ok, i am getting conflicting reports from three different contractors.

i am having a ductless mini-split type air conditioner installed upstairs in my daughters room.

one guy told me they hook it up and thats it, turn it on, good to go.

another guy tells me they pressureize the system, and then its good,

the third guy tells me THEY put a vaccum on it and then it is good.

i dont really care what is the right way, but somebody or two somebodies are lying to me.

help me sniff this out

[poppa]

hook it up, pressurize it, pull a vacuum and yer good to go.

[derrick1623]

well, they are all right. the indoor unit and outdoor unit and lineset are installed, a vaccum is hooked up to remove contaminents from the lines, then the lineset becomes pressurized once the ports are opened.

[The Penguin]

the third guy is really correct. to do a correct installation of a mini split the indoor section and the piping need to be pressurised for a leak check then evacuated to remove the gasses and any moisture present once this is completed then the valves on the out door unit are opened and the unit commissioned. depending upon the manufacture and the length of the pipe run refrigerant may need to be added or removed to ensure peak performance.

it is possible that some people may been skipping some steps this reduces the units life expectancy, and capacity of the unit. it is also possible that the contractors you talked to did not explain the procedure completly even though they will do a pressure test and vac before opening the valves.

[Diceman]

Pressurize and leak check, pull vacuum for short time, open valves and turn it on.

[spotts]

Originally posted by Diceman
Pressurize and leak check, pull vacuum for short time, open valves and turn it on.

Dice is the "Resident Expert" at these. We all still cant get over his amazing skills of running linesets!

[thehumid1]

They are probably all gonna do the same thing, just some have better communication skills than others... It would take a real lack of talent to screw up a mini-split.

And Diceman is the expert on these? I thought it was that toothless first time poster english bloke in the Wall of Pride....but your probably right.

[merken1]

It depends on the line set. If the line set for the unit is precharged and the contractor does not cut it, the first responce is right.

If the line set is cut or they run copper pipe the last one is correct. You need to evacuate the lines if they are exposed to the astompohere. Pressuring the lines checks for leaks and the vacum pump removes impurities and moisture.

I would opt for the precharged lines if it is possible in your installation and request that they not be cut, if possible.

[Diceman]

How do you hook up those precharged line sets?
Most units I saw were flare ftgs.
And about my Fujitsu.........the ones everyone wanted to put their stickers on..........they are just jealous.
Anyway, they didn't see my 1st floor unit, it looked very professional, if I must say so myself.

[condenseddave]

Originally posted by Diceman
How do you hook up those precharged line sets?
Most units I saw were flare ftgs.
And about my Fujitsu.........the ones everyone wanted to put their stickers on..........they are just jealous.
Anyway, they didn't see my 1st floor unit, it looked very professional, if I must say so myself.

Some USED to have Aeroquip fittings.

Personally, every single one I've ever seen have leaked.

I'd discourage the use of precharged linesets.

Fujitsu??????? Is that a compact car or something???

[Diceman]

Like I said.......jealousy..........

[Diceman]

I ain't seen a precharged, quick connect line set in years.

[derrick1623]

i recently installed a nice fujitsu split system, the outdoor unit was shipped to the h.o. with a stiped flare fitting on the port, had to ship it back. ran like heaven once installed though!