A/c. Checking efficiency.

Did you check the cabin filter for being dirty? Without proper air flow
through the AC system, you won't get the cooling you should.

"Mike G" > wrote in message
...
>
> "John" > wrote in message
> .. .
> > Please check your procedure. Bubbles in the refrigerant means you're
> > possibly low. Allow the system to run for at least 10 minutes and check
> > the
> > sight glass. If you see bubbles, add refrigerant until the bubbles just
> > disappear. A sight glass that looks empty most likely is full of
> > refrigerant. Otherwise the low pressure cutoff would have stopped the
> > compressor from self-destructing. If you don't hear the compressor
> > cycling,
> > then most likely you're low of refrigerant.
>
> As I said in my post. The a/c seems to be working properly.
> But, as far as I can see, and Bentleys would appear to confirm it, the a/c
> system in my car doesn't have a sightglass.
> My Celica has one, so I know what to look for.
>
> I know a thermometer in the outlet will show it's blowing cool air. I'm
just
> wondering if it's as cool as it should be. My feeling is that it should be
> cooler.
> To be comfortable on a hot day, around 30C it has to be running at max.
> OTOH, admitted the a/c in my Celica is an R12 system which in general are
> more efficient, max on a hot day would give me goosebumps.
> Mike.
>

"John" > wrote in message
. ..
> Did you check the cabin filter for being dirty? Without proper air flow
> through the AC system, you won't get the cooling you should.

Good suggestion, but the microfilter was changed about 6 months ago, when
the car had a major service.
I saw the old one removed and replaced with a new one, so I know for certain
that it was changed.
Seems no shortage of air. Anything higher than a fan setting of 2, and it's
blowing a gale. :-)
I'll see what a thermometer says before taking it any further.
Mike.

"Mike G" > wrote
> "John" > wrote
>> Did you check the cabin filter for being dirty? Without proper air flow
>> through the AC system, you won't get the cooling you should.
>
> Good suggestion, but the microfilter was changed about 6 months ago, when
> the car had a major service.
> I saw the old one removed and replaced with a new one, so I know for
> certain
> that it was changed.
> Seems no shortage of air. Anything higher than a fan setting of 2, and
> it's
> blowing a gale. :-)
> I'll see what a thermometer says before taking it any further.

I believe that you've already checked that the aux electric cooling fan
is working. One thing you could do is to get a big box fan (36" or so)
and place it in front of the grill to see if that helps the heat transfer in
the condenser. A/C shops do this to ensure that they've got enough
airflow when testing the system's efficiency. In my BMWs, the air
coming out of the a/c vents is about 10 degrees F cooler when the
car is moving.

FloydR

"Floyd Rogers" > wrote in message
...
> "Mike G" > wrote
>> "John" > wrote
>>> Did you check the cabin filter for being dirty? Without proper air flow
>>> through the AC system, you won't get the cooling you should.
>>
>> Good suggestion, but the microfilter was changed about 6 months ago, when
>> the car had a major service.
>> I saw the old one removed and replaced with a new one, so I know for
>> certain
>> that it was changed.
>> Seems no shortage of air. Anything higher than a fan setting of 2, and
>> it's
>> blowing a gale. :-)
>> I'll see what a thermometer says before taking it any further.
>
> I believe that you've already checked that the aux electric cooling fan
> is working.

Oops!. Now I feel very foolish.
The aux fan isn't working, and never has worked, since I bought the car over
2 years ago. It's not siezed solid, but it can only be turned with
difficulty using a screwdriver through the grille.

Until you mentioned it, it had completely slipped my mind. But now you have,
it's the most likely explanation for the a/c not getting as cool as I think
it should.

One thing you could do is to get a big box fan (36" or so)
> and place it in front of the grill to see if that helps the heat transfer
> in
> the condenser.

I picked up a good s/h fan last year, but hadn't fitted it, as it needed a
new resistor as well. Which I now have, so I've no excuse for delaying it's
fitment any longer.
Even without the fan, the a/c does work reasonably well. Hopefully after
fitting it, it will work even better.

Apologies if anyone thinks I've been wasting their time.
Fortunately for me, I'm not always that stupid.

Mike.

"Mike G" > wrote
> "Floyd Rogers" > wrote
....
>> I believe that you've already checked that the aux electric cooling fan
>> is working.
>
> Oops!. Now I feel very foolish.
> The aux fan isn't working, and never has worked, since I bought the car
> over 2 years ago. It's not siezed solid, but it can only be turned with
> difficulty using a screwdriver through the grille.
>
> Until you mentioned it, it had completely slipped my mind. But now you
> have, it's the most likely explanation for the a/c not getting as cool as
> I think it should.

Well, there you go! Glad to have been of help.

FloydR

Mike G wrote:
>
> "John" > wrote in message
> .. .
>> Please check your procedure. Bubbles in the refrigerant means you're
>> possibly low. Allow the system to run for at least 10 minutes and
>> check the
>> sight glass. If you see bubbles, add refrigerant until the bubbles just
>> disappear. A sight glass that looks empty most likely is full of
>> refrigerant. Otherwise the low pressure cutoff would have stopped the
>> compressor from self-destructing. If you don't hear the compressor
>> cycling,
>> then most likely you're low of refrigerant.
>
> As I said in my post. The a/c seems to be working properly.
> But, as far as I can see, and Bentleys would appear to confirm it, the
> a/c system in my car doesn't have a sightglass.
> My Celica has one, so I know what to look for.
>
> I know a thermometer in the outlet will show it's blowing cool air. I'm
> just wondering if it's as cool as it should be. My feeling is that it
> should be cooler.
> To be comfortable on a hot day, around 30C it has to be running at max.
> OTOH, admitted the a/c in my Celica is an R12 system which in general
> are more efficient, max on a hot day would give me goosebumps.
> Mike.

If it's working properly and you'd like it colder, there is a product
called ICE-32 which will do that. It is basically a synthetic lubricant
for R-134a systems. You can install just like topping off refrigerant.
It results in an immediate temp drop of 6 to 10 degrees every time. I
have installed ICE-32 on a variety of vehicles, domestic and foreign,
with immediate results. It also will quiet down a noisy compressor if it
is not a failure noise.
They make a variant for R22 home A/C. It works also, raising the
heating temp (heat pump) last winter, and this summer the cooling temp
is about 4 degrees lower than before.
The only reason I haven't added it to my Z3 is it already freezes me
out. But I'll do it just for reasons of longevity.

Check it out. they have a website.

In article >,
Mike G > wrote:
> Oops!. Now I feel very foolish. The aux fan isn't working, and never has
> worked, since I bought the car over 2 years ago. It's not siezed solid,
> but it can only be turned with difficulty using a screwdriver through
> the grille.

> Until you mentioned it, it had completely slipped my mind. But now you
> have, it's the most likely explanation for the a/c not getting as cool
> as I think it should.

It only makes a difference at slow speeds - say in town running.

--
*I get enough exercise just pushing my luck.

Dave Plowman London SW
To e-mail, change noise into sound.