I had posted last year about my taurus air conditioner having issues,
and I finally just got around to getting a proper set of gauges.
A/C doesnt work on hot days, only cold days. I can hear the
compressor kick in on the cooler days, but never on the hotter days.
A can of refrigerant was added last year thinking that the system was
low. At that time a "low side' gauge was used, because it was all I
All last summer, if I left the A/C on high all the time, it would
work. If I shut the fan off for even a minute, it would stop working.
This year, the A/C will only kick in on really cold days. I now have
high/low gauges. The high side sits at about 75, and the low side is
at between 70 and 85. If the compressor kicks in, the low side will
drop to about 40.
What should I look for?
Magnets work better when they're cold. The compressor clutch has a
big electromagnet to pull in the outer plate. When the facings get worn,
the magnet isn't strong enough to overcome the widened gap. Adjusted
by changing shims between the clutch parts.
Mom's did that too. Fixing the clutch fixed the problem.
Did you check for power at the clutch plug when the system is turned on?
all A/C pressures are load sensitive. load being the combination of temp,
humidity, fan speed and condensor temp.....their are no FIXED numbers you
can use as a bible....that said, with comp. running, clean condensor,
condensor fan running, medium blower speed, windows up my numbers would
be 38lbs/low side....200lbs/high side with an outlet temp about 40
degrees..........if comp. clutch wont close slap it with a broom stick to
see if it will engage. if so you have clutch
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On Fri, 01 Jun 2007 19:04:57 -0700, firstname.lastname@example.org wrote:
The high side pressure should be more like 150 to 250 pounds. Low
side should really be a little lower they you are getting, ideally it
will pull it down to about 25 and then the low pressure switch will
turn off the clutch till the pressure goes back up to 30+. Make sure
you have the valves on your gauges closed when reading pressures, I
left mine open once and it messed up the readings. It may be that you
just have a bad low pressure switch that is sticking and not letting
the system turn back on. The other posters suggestion of clutch
clearance too large is something to check too.
I realized I made a little mistake when reading the pressures. The
clutch wasn't engaged when I did the readings, so it was showing
really high (roughly the outside temperature, which I have read is
normal). When the clutch finally engaged, I had about 25 on the low
side, and 75 on the high side. I let it run for a while before doing
the "official" reading. From everything I have seen, this tells me
that I was low on coolant, since the high and low side were both lower
than they should be.
On saturday afternoon, I added another can of refridgerant. It took a
while for it all to go in, and slowly the high side raised up to about
150 pounds. It was at that point that the can ran out of R-134a. I
have since bought another can, but I have not yet put it in. The
symptoms are now the same as they were last year. The compressor will
kick in and run well for a while, then eventually it stops kicking
in. If I leave the fan on high blowing frigid air, it will go as long
as I want it to. As soon as I shut it off, I get slowly warming air.
I'm going to have to put a meter on it to see if the clutch engaging
wires have voltage to tell me if the clutch is trying to kick in.
Since checking the clutch clearance is a bigger job, is there anything
else I should look at? I'm not looking forward to pulling the
compressor off to get a look at the clutch. Is there any other way to
get at it, as it seems the frame of the car would get in the way?
Since when I was adding the refrigerant, the high and low side was
still low, is it possible I'm still low on refrigerant? I have added
about 2-12oz cans so far. Also, could this be a symptom of a leak?
Thanks for the help so far.
On Tue, 05 Jun 2007 12:37:48 -0700, email@example.com wrote:
I'd try another can and see if that fixes it. If it doesn't then I
would do as you suggest and see if there if voltage going to the
compressor but the clutch not kicking in. If the compressor clutch
seems ok then consider the possibility that the low side switch is
I am working on a 97 Sable with a good A'c system which is charged and
which can have the ac clutch jumped with battery voltage. There is a
module mounted on the battery guard between the battery and the
driver's quarter panel which is a two stage module mounted to a module
via a 1/8 inch foam gasket If I bump the outer part of the
module(closer to firewall) toward the front of the vehicle and the
other part of the module whilethe AC system is on, the ac clutch will
engage and the system will start blowing ice cold. Anybody know what
this module is called? Is it magentetically actuated and can it be
On Jun 5, 3:37 pm, firstname.lastname@example.org wrote:
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