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mm mm is offline
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Default Central Air Problem

On Fri, 06 Jul 2007 11:30:23 -0700, wrote:

On Jul 6, 2:14 pm, wrote:
Here's the latest on my problem. It stopped working and checked the
indoor and outdoor control panels and nothing was frozen.


It was never the control panels that get frozen, it was the A coil
(the evaporator) which is inside the plenum (as they call it, the big
duct coming out of your furnace, which may or may not have a cover you
can take off to look inside. I had to cut a hole in my duct so that I
could look inside. (There are two sides to the furnace, intake and
output, and the A-coil is on the output side, all the time afaik, but
before you make holes, you should be sure that you are at the right
place. If you see two curving pipes going into the duct there, and
the other end of the same pipes go out of the house to the outside
unit, you're at the right end. But I don't think you want to cut the
hole yourself, do you? But if there's a removeable panel, I think
that you could do, although I'm not sure what you woudl gain.

(OT for you, but I probably should have made my hole bigger, but I was
just trying to find out what happened to the water that condensed, so
since I"m a "good boy", I made the hole small. If I ever have to
clean it, I guess I'll have a hole around a hole. I don't even
remember how I patched the first hole.)

It doesn't
look dirty so would the dirt be internal? Do you think it needs more
freon? The outside fan does run and air comes in but just not cold
air all the time.


Please don't take this the wrong way, but you're so clueless about how
your A/C works that you really should call a professional in. Trying
to do it yourself, you're just going to break it worse than it already
is.

If it needs freon, it has a leak, and any freon you add (provided you
manage to add the freon without blowing yourself to kingdom come) will
just leak out. A professional has a special dye and tools to detect
and fix the leak.

The whole discussion is moot, though. All you keep saying is "IT DON'T
WORK." There is no way to diagnose the problem without more
information, and even then, there still may be no way to completely
figure out what is going on without physically being there.


You're right in about all of this, but you shoudl have stopped....

You probably wouldn't make these little errors if you had reviewed
this an hour after writing it.

A little lesson on A/C: Air doesn't "come in." You are not getting
cold outside air when you turn on the A/C. The outside unit compresses
the freon and cools it.


You mean, and heat radiates from it. It's no cooler in temperature
than when it came into the outside unit (and I'm pretty sure it's a
little hotter.)

The compressed freon flows to a radiator


It's a lot like a radiator for sure, in that it has fins and transmits
heat, except that radiators *radiate* heat, whereas this thing absorbs
heat, so I"ll bet no designer or pro would call it a radiator. Still,
it might be a good term to use with the OP because a radiator is
something she's probably experienced with, from cars.

inside your ductwork in the house, where it is allowed to expand. When
it expands, it gets really cold. Your furnace blower sucks air out of
your house,


Not out of the house but into the big duct, which is still inside the
house. You know what you mean, but she may run around looking for
something out of the house. Well it might be true if your furnace was
out of your house, if you count the attic or the garage as out of your
house, but even then I think most ducts where cooling is done are in
the house.

blows it through this radiator where it gets cold, then
blows it back into your house. The cold air you feel is inside air
that has been cooled.


Doesn't blow it back into the house either, but you call it inside air
in the next sentence, which helps.

This radiator in the ductwork (called the condensor IIRC) is the part


Called the evaporator. The condensor is in the box outside, with the
compressor. If you compress a gas enough, it will turn into a liquid,
which is what condense means. The gas becomes hot as you compress it,
but cools off almost to the outside temperature, because it is
outside.

The easiest way I remember this is that when you take the valve out of
tire, or when you release your fingers from a balloon, the air coming
out is cool. That's because it's no longer compressed. So the
converse is also true and when you compress air or any gas like freon,
it becomes hot. (Actually when you fill a tire or some smaller
things, you can feel that they become hot, plus the hose from the
pump, even a basketball pump.)

that may be full of crud and/or frozen.


Both inside and outside fins can be dirty. Only the inside will be
frozen because of lack of freon.

Usually it is located near the
furnace because that is where the fan is.


And the ducts, if one has a furnace that uses ducts.