Highlight text to annotate itX
All right, today I'm going to be showing you how to charge up a unit that's low on freon.
This particular one, when I feel this suction line, the low side line, it's not even cool.
It's room temperature here, so we're low on freon.
Got my standard set of gauges here, and I've calibrated my gauges so that they show zero.
And I got my refrigerant can of freon on top of the unit. So I'm going to go ahead and
get set up here and show you how to hook this up.
What we're going to do is we're going to take the blue low side line, make sure both of
our valves are off here. Because of the low side lines, I'll go ahead and hook up my line
here. Now, you always want to wear gloves anytime that you're working with refrigerant
to protect yourself from frostbite.
And now looking up at my gauges, I can see it's only at 20, which is too low. And the
first thing we want to do, the thing that's the worst for an air conditioning unit, is
get moisture on the line. And moisture's obviously contained in the air, so we want to bleed
any air out of the line. And the way we do that-- this is called a de minimis release,
and we're going to purge any air from the line by cracking the valve right here and
let a little bit of the freon out to purge the line. So now there's no air in the system.
The high side line right here, we're going to loosen the schrader valve cap, again, listening
that would indicate that we have a leak there. So I'm going to hook up my high side line.
Which is kind of tricky on this unit, but that's OK.
Going to lift it up here. And on our high side, up here at the gauges. We're going to
again release a little bit of refrigerant to purge that air from the line so that we
don't get air in the lines.
Now what we're looking for on the high side is ambient temperature plus 30 degrees. So
We're looking for ambient temperature, plus 30. So we want it to be about 135 on the high
side. So obviously we're pretty low here.
So our middle line, we're going to take and we're going hook this up to our refrigerant
can. I'm going to angle this up so you see it here. Then we're going to turn thew refrigerant
can on open it up. And again, were going to come back down to our gauges. We're going
to crack the port here to release the purged air from the system.
Now we're ready to charge the unit. If we didn't purge the air and I opened the line
to charge the system, that air is going to go into the system. And when the moisture
in the air mixes with the refrigerant, it's going to turn into acid and it's going to
cause us leaks and all sorts of trouble. So anyway, I purged the line, we're ready to
charge. So I open the line, and you can probably hear the refrigerant going into the system.
Now here I'm feeling the line with my wrists in the suction line side. I can usually tell
by feel when it's starting to get cold. But what we're looking for is for it to flash,
when it just flashes really ice cold, and to charge the unit up. Also, again, we're
looking for ambient plus 30 degrees on the high side, so this can take a little while.
I can show you a few little tricks on charging the unit up. One way to get it to charge faster
is if your compressor's hot to the touch on the top here-- which this one is, it's been
running low on freon-- you can pour a little cold water on the top of the compressor, being
careful not to let it touch the electrical contacts. Or if you had an ice pack, to put
an ice pack on the compressor-- that'll speed the refrigerant charge.
Also another way is having shorter hoses helps. Sometimes these hoses, they send you with
a six foot hose line and that's going to cause you to take longer to charge the unit. I like
these little short ones. These are three feet-- perfect for me.
But obviously, there are some situations where you need the longer hoses. And some people
might disagree with me, but anyway, this is how I like it. Makes it nice and easy for
It's pretty hot out here. I'm going to drink a little water myself. A little water for
me, a little water for the compressor here to speed things up. You could see it just
sizzling off-- that's how hot this compressor is. It's just been running low on freon.
So we're only at 110 on the high side, this is going to take a while. On the low side,
looking here at the dials, you've got different color dials. The inside one is purple for
R502. And this green ring is what we're looking for to match the can of our refrigerant, which