A/C not cooperating.
 

Yesterday we tried to charge the A/C. For some reason the freon wouldn't go past the valve. We pulled the compressor, verified that the service valves were open, Hooked the can to the valve and verified it was working, and put it all back in the car. But when we start the car and hook the can to the valve it spikes the gauge and nothing makes it into the system. For some reason the freon isn't getting past the valve, even though it worked fine when we had it out of the car? We even tried two different hoses. Couldn't get it to work.
Don't have time to mess with it till afer the move. So all you OC guys put on your A/C thinking caps. You have about a week to think it over before I start calling you out.;)

If you are using refrigerant hoses the angled end of the hose goes on the suction side of the compressor. In the hose there is a stem that will engage the schrader valve on the compressor.

I think Brian may have the answer -- in the hose end is a little plunger that's supposed to depress the valve and allow the refrigerant to pump from the can into the compressor. Check to be sure you haven't installed the hoses on your gauge manifold "bass-ackwards" (i.e., with the little plunger at the manifold end rather than at the compressor end of the hose).

Good luck.

Whatever you're using to hook the freon to the compressor, junk it and get something else. Also check the high side and low side BEFORE doing anything. Make sure that there is not a blockage in the system.

When the enginge lid is open and the AC is on, you should run a small shop fan across the condensor coils to keep the system from getting too hot and burning out the compressor.

Remember to evacuate the system and pull a vacuum to 30in for at least 45 mins.

I used to fly into Warsaw Indiana all the time!!! I wish we could have gotten together and had one or 20 and talked cars.

About your AC problems........just remove it and you won't have to hassle with it. :)

Brian

Hey Shawn

Did you check out this post http://forums.pelicanparts.com/porsche-911-technical-forum/285279-c-wont-recharge.html

If you have the old York compressor they have stem valves and not shrader valves. You need to open the stem valve in order to access the system.

If you converted to 134a refrigerant and have the quick connect fittings, check the quick connect fitting from the gauges. On some 134a manifold fttings, once you attach the quick connect fittings to the system, you need to turn a tumbscrew to open the valve.

Like I said to you in a previous post if you don't have someone who know what they are doing, don't mess with the a/c because you can hurt yourself.

If you are in the Land of the World Series Champions, give me a shout and I could probably help you with the a/c.

Re: A/C not cooperating.
 

Thrown'n da hamer,

Have you pulled a vacuum on this system?

You are not using one of those a/c refrigerant "kits" from one of the bigbox auto parts stores.... right?

You are NOT connecting the hose from the refrigerant can to the "high" side connection on the compressor (compressor to condenser)
with the engine running... right! :eek:



!!!!!!!!!!!!!!!!!!!!!

How come everytime I post a question everybody climbs under the desk and covers thier ears?:D

Please re-read the original post. We used TWO different hoses and neither one would let freon into the system while the compressor was in the car. We pulled the compressor out of the car. We verified the service valves were open and while it was sitting on the garage floor verified that the freon was getting past the valve. IE we hooked the can to the valve and blew a small amount into the compressor and out the opening that hooks to the hose. I had a liscensed A/C tech at my house that is allowed to discharge 50 ounces of freon a year so no wigging out.

The system is void of freon, I replaced the dryer and changed the compressor oil over for the R134a freon. If I can assume the valve works since it worked on the garage floor then there must be some kind of blockage somewhere.

Your goint to have to do the obvious. Test each component and hose seperately. You might as well run flush fluid through to do it. Remeber not to run flush fluid through the dryer or expansion valve.

Whoah, someone missed their valium or coffee dosage.
We can't read minds through the threads.
ASSUMING your "ac technician" knew what they were doing you would not be posting here.

So, how long did you pull a vacuum on this system?
If you did pull a vacuum, did the low side gauge register a max depth rather quickly?

Is this a Nippon or York?

Just so no one reads what I wrote out of context I am reposting my statement as it was meant to be read.

I have never taken any valium but am a little short on coffee at the moment.

The compressor is the original York.

The A/C tech that came to my house is a good friend of mine and runs a successful business. He came over to help charge the system assuming everything worked and it just needed a charge. He has never worked on a Porsche A/C system before and wanted to verify the service valves were open before we started. He said if the service valves were closed it would show vacuum but only be pulling vacuum on the hoses. He hooked the bottle up and nothing went in. So he turned the valves all the way in and nothing went in either. At that point we pulled the compressor to see what was up. The freon went in when the compressor was on the garage floor with the service valves turned all the way out. Seemed odd. We put it back in the car and no freon would not go into the system. He didn’t come prepared to do a complete tear down of the system and troubleshooting. He spent more time than he had allotted and had to go to his son’s baseball game. So after he left I posted the question.

Capt. Carrera, Thanks. That’s what I figured. I don’t have time right now. I suppose I will have to address this after the move.

Ok, so I've had my first 16 oz of coffee and I'm chilled.

The York has "service valves" on the hose manifolds attached to the compressor. You connect your service hoses to the R12 ports on the manifold. The "service valves" will block off in the manifold between R12 port and compressor. Turned fully CW closes, turning CCW opens.
So, if the service valves were closed and you tried to pull a vacuum on the system you would only be pulling a vacuum between your service gauges and the hose connection at the manifold on the compressor.

Which leads us to the unanswered question.... did your ac tech hook up a vacuum pump and pull a vacuum on the system" and if yes where the service valves open before you tried to put refrigerant in the system?

We never got to that point. He said the valve is usually open CCW but wanted to verify before he put the vacuum to it.

I have also had my dose of coffee and fell much better now.

Here is what you can do:

Assuming there is not refrigerant in the system.
Install a new drier.

Add 6-8 ounces of ester oil to the compressor.

1) Hook up your service gauge hoses to the compressor manifolds.
2) Connect your vacuum pump.
3) Open the service manifold nuts "nearly" fully CCW. I say nearly full CCW because I recall on some if you go full CCW it will close again.
4) Pull a vacuum for 3 hours.
5) Lock up your service "gauge manifold" valves fully CCW and turn off the vacuum pump.
6) Take a small tip marker and mark on the face of the low side gauge where the needle is, should be close to -30 in.
7) Go have a Becks or cup of java and wait 20 mins, not more than three Becks.
8) After 20 mins. see if the gauge needle on the low side moved back toward "0". If not and it is still where you made the mark then you have a good "gross leak" check. If if moved back toward "0" then you have a leak somewhere between the service guages and the cars system.
9) If the gross leak check was good THEN you can put the refrigerant in the system. In order for the refrigerant to go out of its container into the system the system pressure must be lower than the pressure in the refrigerant container.
10) You can do an initial charge or partial charge through the high side manifold WITH THE ENGINE OFF using liquid (refrigerant can upside down), or if your expert has a heater blanket for the refrigerant can you do do liquid or gas..... making your final charge using a P&T chart, your expert should know.

I think you should take your car over to his place and have him hook up his equipment to diagnose what's going on. I assume you connected the refrigerant to the low side valve. Sounds like he tried to charge the system (liquid) through the high side valve (no, no and dangerous).

What are the gauges reading?

Or maybe the compressor is blocked or not rotating (check the clutch?). Even then, refrigerant would still fill up the low side of the system (low pressure hose > evaporator > expansion valve).

BTW, Porsche A/C has the same basic components and works the same as any A/C system. Nothing personal, but does your friend own or work at his A/C shop?

?
Sherwood

<i>BTW, Porsche A/C has the same basic components and works the same as any A/C system.</i>

.....hmmmmm, no.
The 911 uses a drier and an expansion valve to meter the refrigerant, the compressor is cycled by the thermostat directly. Other vehicles can have orifice tubes with accumulators and can cycle the compressor by various combinations of switches and sensors.

Sherwood, I realize in California a 911 is a common sight. In northern Indiana I may as well have a pre-war Bugatti. He just wanted to be sure he understood the system. Most cars he has dealt with don’t have a A/C condensor on top of the engine.

I am moving on Saturday. I don’t have time to deal with it at the moment. After the move from a 911 perspective I will be in much better hands.

A MOVE!

who's bringing the beer and burgers?

I will bring both if you charge my A/C.;)

"Other vehicles can have orifice tubes with accumulators and can cycle the compressor by various combinations of switches and sensors."

Basic A/C components are the same (compressor, condenser, receiver/drier, expansion valve, evaporator). There are variations of control mechanisms, and the receiver/drier is now placed inside the condenser on some vehicles (sub-cool condenser). Those other systems are just a variation of the basic A/C system.

I wonder why the A/C tech was thrown off by the location of the condenser? It doesn't matter where it is as long as it transfers heat to atmosphere.

I hope you get it working soon.

Sherwood

Hey Thrown Hammer,

my hat is off to you in keeping up the Porsche standards in No. Indiana.

Kuel: How do you know when you've added enough compressor oil to the 134a (ND Compressor), and do you recommend the refrigerants with o-ring conditioner, or the straight refrigerant? My apologies to the others, I don't mean to hijack this thread.

On the ac oil mama P published a suggested amount of oil to to put in for each component however I don't recall the hoses being noted, and their list is pretty close to the auto ac industry suggested amounts, for example P lists:
Compressor 2 oz
Evap 1.6 oz
Condensers .8 oz each
Drier .4 oz

Depending upon what you read or how old the fart is that is writing you might gather:
Compressor 2-4 oz
Evap 1 oz
Condensers 1 oz
Drier 1 oz

So the recommendations are close enough. But they don't address the 40 feet of hose of which two lay under the car.

I can say that from what we have done over the years if you were to do a totally fresh install or even just the hose compressor and drier, usually 6 oz works just fine.
Always better to have too much oil than too little.

"Conditioners" or "revitalizers" are great for the scalp.
I use them all the time and they make my head of hair look 10 years younger. However, I would not recommend these monkey oils for your ac system. MAC Air (mobile air conditioning society) did a report a year or so ago on "sealants" and such and stated "stay away", they clog up the system. To get a good idea, find a sink or drain where some on is using these hair tonics and you will find sludge in the trap. Same with the AC system.

And, when an elastomer is going south it is going south, nothing is going to put years back into an oring (alike power steering rack sealants, they don't work).

Hey Shawn

First off did you put 134a fittings on the low side and high side valves? If not that a NO NO. The next person that service the car if you ever sell it will not know that the system was converted.

If you did, it must have been a hell of time getting them to fit. I need to remove the a/c compressor just to install a regular set of R12 gauge when I service my a/c.

When you open the stem valves to gain access into the system you don't crank them all the way open or else you do what they call front seat the valve. When you crank it all the way back to close the valve it is known as back seat the valve. You want to be somewhere in the middle so that you have access to the system.

I would have keep with the R12 refrigerant if I was going to use the old Yorkie compressor instead of upgrading to a wobble plate compressor.

How far is Warsaw Indiana from the Windy City?

I believe it is the opposite. To lock up your service manifold so that you isolate the yellow hose from the system (Vacuum or charge) you need to turn your service valves fully CW.

"Ruffer", to clarify:

On a York compressor, the sevice manifold valves attached to the compressor have a valve seat at the end of the shaft.

Turning the square shaft on the <b> compressor's </b> service valves CW moves the seal on the shaft inside against the seat inside the manifold valve.... which closes off the passage between the compressor port and the a/c hose (either high side or low side). Turning the square shaft CCW opens the passage between the compressor port and the a/c hose.

If you were to remove one from a York and look inside:

http://forums.pelicanparts.com/uploa...1149078748.jpg

<i>3) Open the service manifold nuts "nearly" fully CCW. I say nearly full CCW because I recall on some if you go full CCW it will close again. </i>


<b>RECLARIFIED</b>
5) Lock up your service "gauge manifold" valves fully <b>CW </b>and turn off the vacuum pump.
6) Take a small tip marker and mark on the face of the low side gauge where the needle is, should be close to -30 in.
7) Go have a Becks or cup of java and wait 20 mins, not more than <b> two </b> Becks.
8) After 20 mins. <b>REOPEN </b>(turning CCW) the service gauge manifold valves fully see if the gauge needle on the low side moved back toward "0". If not and it is still where you made the mark then you have a good "gross leak" check. If if moved back toward "0" then you have a leak somewhere between the service guages and the cars system.

http://forums.pelicanparts.com/uploa...1149079657.jpg

Kuehl

http://forums.pelicanparts.com/uploa...1149078748.jpg

There are no "Schrader valve" in a York Comprssor as fitted to a Porsche 911. The Schrader valve identified in picture is just a flare fitting that you attach a hose with a flare fitting to.

If you crank the stem all the way to the top, the round disk as shown in the picture will be up against the valve seat preventing refrigerant from entering the compressor, or preventing a vacuum pump from evacuating the system. The round disk must be somewhere between fully close and fully open to allow you to service the system. Fully open is where you want to be after you have completed servicing the system.

Fully close is when you pump down the system so that the refrigerant is pumped into the condenser and you can remove the compressor from the system by removing the stem valves from the compressor.

In your other post you inform Shawn to "Lockup" the manifold by turning the manifold valves CCW which is incorrect, which I pointed out to you and which you corrected in your later post.

If Shawn had turned the High side valve CCW as you advise to (Lockup the manifold), while the engine was running and a can of refrigerant attached to the gauge set, the can could have exploded.

When giving advice to DIYer you need to reread the posting so that the information that you are giving is correct.

I would hate to see someone hurt because of typo in the instruction.

<I>"There are no "Schrader valve" in a York Comprssor"</I>
When we, (I) say Schrader Valve, "I" used the term in a visual sense as most refrigerant service ports we see on compressors (excluding R134a adapters) frankly look like August Schrader's valve stem originally designed for tires. I guess in a semantical sense I am guilty as charged for using the term "schrader". However I'd rather take the bullet and direct the do-it-yourselfer to look for something they may be more comfortable of finding rather than saying the refrigerant service valve perse.

However, to be more concise, "YES" there are Yorks out there with ... complete "schrader" valves having a "poppet " valve inside. Why this unexpected phenomena you may ask? Unmöglich ! Well new OEM service flange valves are expensive or difficult to find. So you have aftermarket. And, below is a picture of the same service flange valves. If you look at the valve on the right it has an "valve core" aka "poppet" which makes it a full fledged Schrader Valve.

http://forums.pelicanparts.com/uploa...1149169708.jpg

<i>If you crank the stem all the way to the top, the round disk as shown in the picture will be up against the valve seat preventing refrigerant from entering the compressor, or preventing a vacuum pump from evacuating the system. The round disk must be somewhere between fully close and fully open to allow you to service the system. Fully open is where you want to be after you have completed servicing the system. </i>
Again, Yes and No.
Assuming the service flange valve does not have a schrader, when the square stem shaft is turned fully CCW the seal is pulled away from the valve seat on the opposite end opening the passage between the vehicle's hose connection and the compressor's top flange port.
I think we noted more than enough that when opening the valve CCW you should not drive the square valve stem all the way CCW as it limits the flow passage to the "schrader valve" (aka 1/4" flare service hose port). However there is no formal or functional valve seat designed on this side of the shaft (between the 1/4" flare and internal shaft) that provides adequate sealing to shut off the passage from inside the service flange valve and the hose from the service gauge manifold hoses, though flow is nearly cut down to a dribble as we noted. When you turn the square shaft fully CW the seal on the end of the shaft seats to close off the passage between the vehicle's hose connection and the compressor's top flange port.

<i>In your other post you inform Shawn to "Lockup" the manifold by turning the manifold valves CCW which is incorrect, which I pointed out to you and which you corrected in your later post. If Shawn had turned the High side valve CCW as you advise to (Lockup the manifold), while the engine was running and a can of refrigerant attached to the gauge set, the can could have exploded. </i>
hmmmmm..... let's see.
1st post to warn the DIYer reads:
"You are NOT connecting the hose from the refrigerant can to the "high" side connection on the compressor (compressor to condenser)
with the engine running... right! "

further post reads:
"The York has "service valves" on the hose manifolds attached to the compressor. You connect your service hoses to the R12 ports on the manifold. The "service valves" will block off in the manifold between R12 port and compressor. Turned fully CW closes, turning CCW opens."
Well yeah, a bit of confusion here. I guess we should have stuck with the Becks rather than the java.

further post reads:
"3) Open the service manifold nuts "nearly" fully CCW. I say nearly full CCW because I recall on some if you go full CCW it will close again."

further post reads:
"5) Lock up your service "gauge manifold" valves fully CCW and turn off the vacuum pump."
I agree, we'll change this to read CW. However had the DIY gone CCW and turned off the pump, before he finished his first Becks the system would have gone to atmosphere rather quickly as most pumps and service sets do not have a shut off vavle between the pump the service gauge set. And that post did not include the complete steps to operating the service gauge valves for the charging procedure. Again high side pre-warning was stated in first post.

<i>When giving advice to DIYer you need to reread the posting so that the information that you are giving is correct. I would hate to see someone hurt because of typo in the instruction.<.i>

I agree as well, and I appreciate your kind critique.

I just hope "we" have in a constructive way helped this DIYer.

Kuehl's right. On my York, the low-side (suction) backseat valve system had a Schrader valve. This confused me at first because it's not needed presuming that the backseat valve is OK.

Thanks for the receiver/drier, by the way, kuehl.

Brian

Not a problem,
just remember that the "backseat valve" or by CCW all the way
"may not" provide a perfect seal between your service gauges and the "schrader" "1/4" port.