rev up your engines, okay it's getting hot outside and you want to stay cool in
your car, today I'm going to show you things you can do yourself to make sure
that your air conditioning is going to work this summer season correctly, so I'll
explain all about how an air conditioning system works first
now air conditioning is just a heat pump, it sucks the hot air out of the cabin of
your car, and then it blows that heat using the a/c condenser in front of your
car's radiator, the condenser is hidden in here in the front and behind it is
the radiator and the cooling fans that cool both the radiator and the air
conditioning system, now in modern cars of course it's all computer control, but
it's still the same basic idea, the refrigerant is compressed by the
compressor here, it's cool that a car thing is always the name means what they
actually do, and once the refrigerant it's compressed, it goes to the lines
into the condenser in the front, where the heat is sucked away by the cooling
fans in the radiator system, then a high pressure refrigerant goes on the skinny
little line into the evaporator inside the car, here's an evaporator, when the
high-pressure gets into the evaporator, it expands and as it does, it sucks in
the heat from inside your car where you're hot, now this big tube here, it's
connected to the evaporator inside the vehicle, and it takes the refrigerant out
and sucks it back into the compressor down here, and the compressor in an
endless cycle, then compresses it again, it goes through the condenser where it gives
off a lot of heat, and then goes back into the evaporator, so it's basically an
endless cycle of, compressing refrigerant, then heat gets sucked out in the front
of the car, then that refrigerant goes inside the dash, where it expands in the
evaporator, and it sucks the heat out of the car, then it compresses that again
and goes back to the condenser which gets rid of the heat, it just keeps
sucking heat out of the car, now when made correctly it's a very reliable system, but
there are things that you need to check before summer gets
hot, and it doesn't work anymore and you get mad, and the first thing is make
sure your cooling fans on your radiator are both work and fine, because if they
don't suck all that air through there the engine can overheat, the pressure can get
too high in a compressor system, you need to make sure both fans work, so test
them like this, turn the AC on full blast and let it run a few minutes, you want to
make sure that both of those cooling fans are coming on and off, they won't
stay on the whole time, but you want to make sure they both work and blow good
you can see this one's blowing good and over here this one's blowing good too, now it
gets really hot here in Texas in the summer, and I had many customers over the
years say, my AC doesn't seem to be blowing cold enough and I check and what
was happening was, maybe one of the fans was blowing, but the other one wasn't, so it
didn't get enough airflow, you got to make sure that they're both working fine
and blowing a lot of air when it gets hot outside, now the next thing to check
is the cabin air filter, believe it or not, many modern cars inside the glovebox
have a filter for the AC system, you have to fiddle with the glovebox , it just
plastic so it's real easy, out it comes and inside this little panel you take it off
voila there's a filter, and this car is parked under a tree, so I got one of
these reusable ones, you can see there's a lot of crud coming out of it, you can
hose it down and clean out and use it over many times, and you wouldn't believe
how many times I'd have a customer come to me and say, oh my AC is really working
poorly and what happened was this thing had been in there for three or four years
had never been touched, it was full of crud and hardly any air was getting
sucked over the evaporator, so check your cabin air filter if you have one and if
you're like me and park under a tree, clean it all the time and when you're
done the cover just snaps right over and you snap the glovebox back in, and this
is one of the few times I like plastic, because you can just bend it by your hand
and snap it back in place, you know need a bunch of tools to take the stupid thing
apart with now, the next thing to check as nutty as it sounds, is the car's
battery and here's why, now this Lexus maybe 17 years old, but
everything's computer-controlled, even on the
AC system, so if you don't have the correct voltage coming in from the
battery, that whole system can go bananas and start doing really strange things
and not blowing really cold air, you want to have your battery load tested just to
make sure it's still good, takes less than a minute to hook it up and run the
test, in this case it says replace battery, because it's too weak, and it makes
total sense, because my wife said, the AC doesn't seem to be blowing as cold as it
used too, well wasn't getting enough power, I'll just change the battery
now all cars lose a little bit of refrigerant as time goes on, because they
have a compressor that has a shaft and there's a rubber seal, the rubber seal
has to leak a little, so that the oil inside can lubricate the seal, if the
seal ran dry, it would burn out really fast, so they all leak a little bit, some
might only need refrigerant every, ten years or so, but they all eventually run
out, a professional uses gauges to see if it needs more refrigerant, but here's a
good check, if you find that the passenger side is getting reasonably
cool, but you go over to the driver's side and it's not as cold, that often
means you're low on refrigerant, because in this case, the evaporator is inside
here, so this side gets to the evaporator first, so the coolest air will come out
here and then when it gets to the other side, it won't be quite as cool, so the
air blowing over here won't be as cold as it is on the passenger side, that's
often a sign that you need refrigerant added to your system, now if you have a
set of a/c gauges and know how to use them, go ahead and add your own refrigerant, but
please don't go buy one of those little cans at the store and start adding it on
a guess, because modern systems, they can be off even half an ounce and they're
going to have problems if you put too little or too much, you can destroy a
system, so don't just willy-nilly decide oh I'm going to try to put some refrigerant
in, you can do some serious damage that way, and really if you want to mess
around with this stuff yourself, you can get a set of decent gauges for 50 60
bucks, now the last thing you can check is the condenser itself, now this is really
handy, because on this matrix the condenser is open, as soon as you open
hood there it is, if it gets covered in bugs, you can clean it off with a little
water, hydrate them, and then squirt them off, and then you're going to have a much
more efficient condenser, and since the condenser is in front of the radiator,
it's the first thing in a car to get bugs and mud and crud and sometimes I've
seen plastic bag stuck in them, most cars aren't open like this when you open hood
many of them are hidden behind grilles and stuff, and you can't see in that well
so get a flashlight and look around, if you see an old garbage bag stuck in there or
a bunch of bugs, get it out of the way because if you lower that air flow, your
AC goes whoop, the pressures go too high and it's not going to work right, so now you
know how to get your car's AC ready for this hot summer weather, so if you never
want to miss another one of my new car repair videos, remember to ring that Bell!