a/c temp switch question?

ertech · 05-26-2010, 11:43 AM

trying to probleshoot my AC system.if my compresor is on does this mean that the switch works?

Hugh R · 05-26-2010, 11:48 AM

Probably, you should see the clutch locked up and spinning.

ertech · 05-26-2010, 01:03 PM

so if the clutch works than the switch is ok?
If the ball of the driyer is on the bottom of the glass does it automaticly mean I have enouf freon?

86 911 Targa · 04:33 PM

Quote:

Originally Posted by ertech

so if the clutch works than the switch is ok?
If the ball of the driyer is on the bottom of the glass does it automaticly mean I have enouf freon?

What issue are you trying to resolve?

You have not given us much to work with.

No vent air?

No cold air?

No fan?

And what is your model/year?

Do you have a multimeter?

Gerry

Here's a circuit if you have an 86-87 3.2.

ertech · 05-26-2010, 04:50 PM

hERE IS MY PROBLEM . CAN NOT GET UNDER 60 f AT THE VENTS . GOES AS HIGH AS 80 AT THE VENTS . THE OUTSIDE TEMP IS AROUND 80 but very humid. the ball in the drier is on the bottom . the clutch works . is this normal?
sorry for the caps.
Thanks
ps 89 930

Mitch Leland · Mitch Leland's Garage

Have you looked around to see if you have some greasy spots where your hoses might be leaking, or your compressor has thrown a ring of grease/oil out? Sounds like you're low on Freon to start with. You might have other problems, but if your compressor is working and the clutch is engaged then that's a start.

To double check the A/C compressor: You can have the engine running with someone in the car and another person looking at the A/C compressor, when the driver turns the fan and temp switches on you'll see and hear the compressor clutch engage.

ertech · 05-26-2010, 06:20 PM

what hapens if there is to much freon in the car?will it still blow cold?
the ball in the sight glass on the dryer is on the bottom .
Thanks

Mitch Leland · Mitch Leland's Garage

If your compressor is working and you're not going to re-charge the system yourself, and I wouldn't recommend it for the casual DIY'er, it might be time to take your car to the local A/C shop and see what they have to say. I'm not sure how much more can be added here...

If you hit the search button there's reams of A/C information about pressures and charging your system so when you take your car to the shop you can talk intelligently about the needs of your A/C system. Read on...

It might help if you told us where you were located...

86 911 Targa · 05:30 AM

+1 On Mitch Leland's post.

At this point, this is not a DIY fix, as you do not have the necessary tools.

Your system need the attention of a qualified A/C tech who will perform various tests such high/low side pressures, vaccum check, leak test ect..

If replacement component are required, please check my recent post (5-15-2010) on this subject.

Good luck,

Gerry

ertech · 05-27-2010, 09:49 AM

well i put a bottle of freon i had in the low side . now the temp is around 55-60 . the ball is still on the bottom at adle but when i rev to 2000 the window fills up and the ball goes up . do i need another can?
thanks

86 911 Targa · 05-27-2010, 04:44 PM

Quote:

Originally Posted by ertech

well i put a bottle of freon i had in the low side . now the temp is around 55-60 . the ball is still on the bottom at adle but when i rev to 2000 the window fills up and the ball goes up . do i need another can?
thanks

As per our telecon, you have a leak in you A/C system.

Conduct a leak test prior to any other analysis.

Good luck,

Gerry

Hugh R · 05-28-2010, 02:40 PM

You had a bottle of Freon, was it R-12 or R134a? If the system was R-12 and you put R-134a in without the right oil, you'll toast your compressor. Also sounds like it was/is an R-12 system since you have a sight window to see the ball. Different receiver/drier than one for R-134a.

kuehl · kuehl's Garage

ertech,
It sounds like you were saying the clutch's outer hub was spinning with the clutch pulley (what the belt rides on), the two come together when the clutch is 'engaged' and working. If the pulley is spinning and the outer hub is not then the clutch is not engaged.

It sounds like you said the drier's ball was not high in the site glass but rather low, you have to check this when the clutch is engaged and the compressor is pumping the refrigerant (gas) through the system.

If you added a can of refrigerant and the vent temperatures got colder then the answer is you were low on refrigerant.

Do you have too much refrigerant in the system, I'd say no however you don't want to try to test that idea.

The proper way to add refrigerant or charge the system is not by simply adding a can or two until the ball floats. What you need to do is have the system evacuated to remove non refrigerant gases (air) and then properly charged using a known amount of refrigerant (say by using a refrigerant scale or a machine that can meter it out so you know how much you are putting in), and to use a set of gauges to check the pressures.

The problem you can create if you are not aware of the procedures, for example, if you don't have enough refrigerant in the system and you operate the compressor you can damage it because the stock system does not have a pressure switch to prevent the compressor from operating when system pressures are low (the compressor needs a flow of refrigerant oil which is carried through it by the refrigerant.... like an old two stroke engine). If you mix refrigerants you won't achieve good performance, and the different refrigerants require different types of oils. These are just a few samples of problems and not the worse.

I'd say if you needed to add refrigerant such as you have then you have a system leak, hence adding more refrigerant is a waste of time and money.

Time to visit a porsche shop that is good with ac work.