DIYbanter - View Single Post

DT

In article ,
says...

Interesting.
Where did you get your A/C tools from? Straightforward to use?

I thought the lines had to be hard brazed/soldered.
Isn't flaring asking for trouble?

I would love to be able to do this myself. Really want to put the whole
house on a bunch of minisplits. Got central A/C w/ essentially zero zoning,
and it's killing me.

Flared line sets are the norm for mini-splits, every one I looked at came that
way. The higher priced ones may have dry-break quick connects, although the
flared sets are also called 'quick connect' by many sellers so you really need
to ask questions about ones you are interested in. Mine has been running a year
and a half, fine so far, the brand name is Celiera.

I can't see any differences between the different units I was shopping for. The
wall units are identical, they all use compressors from the same 1 or 2
manufacturers, the controls work the same, etc. The refrigerant is stored in
the outdoor unit, and will purge and fill a specified maximum line length
(usually 24 feet or so), if you need longer lines, you will need a pro to fill
it and add more for any of the units.

You don't need any HVAC tools if you are willing to go with the
standard installation method. You hook up the lines, look your line length up
in a chart, set the valves in a certain sequence and finally purge the line-set
and indoor unit by opening the shut off valve a quarter turn for X number of
seconds. This is calculated to purge out the air, but shut off just as the
refrigerant comes out.

Not a precise method in my mind (Hell, I'm not even sure if it's legal anymore,
but that's the factory method) so I evacuated everything and filled into the
evacuated system. I would suggest that is always a *better* way to go, since
then you can be assured the flares are OK if they hold vacuum. I do have a
lot of experience with flaring lines for a variety of exotic fluids so I am
pretty confident with it. You could also add Voishan washers under the flares
if you wanted, but soft copper seals quite well.

My vacuum pump is just a small Kinney lab pump, but HVAC pumps are readily
available and are not too expensive. Many people use salvaged refigerator
compressors for occasional HVAC use. The refrigerant on my unit uses the same
fittings as R12, standard 1/4" flare, so it is easy to hook up. The new higher
SEER may use a different fitting, they have a different refrigerant.

Dennis