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HomeTech Articles > Porsche 911 Conditioning Frequently Asked Questions

Guest Technical Article:

Porsche 911 Air Conditioning
Frequently Asked Questions


Well here goes; FAQs on Air Conditioning in the Porsche 911 Family:

1. Let's start with some basic nomenclature (old Army word)

a. Evaporator; Box containing the coil of tubes and fins that gets cold and a fan that moves that cold air towards you. An expansion valve at the inlet of the coil meters the flow of refrigerant by measuring the temperature of the outlet pipe.

b. Compressor; Pump that draws the Freon (R-12 or r134A) from the Evaporator that is now a low pressure Gas and compresses it to a high pressure Gas.

c. Condenser; A coil of tubes and fins set in a flat sequence designed to release the heat that the freon has picked up in the Evaporator. This must be placed in the air stream of the car or at least have a fan to cool it. To a point, you can't have too much condenser.

d. Receiver/Drier; A small metal can or tank situated between the Condenser and the Evaporator that does three things; stores extra freon, filters out impurities, and removes moisture that may be in the system. Contains a desiccant (of many different materials) which can trap only a small amount of moisture.

e. Hoses; Connect all the components together. Usually in three sizes, #10- from the Evaporator to the Compressor, #8- from the Compressor to the Condenser, and #6 from the Condenser to the Receiver/Drier to the Evaporator. Perhaps the best investment a 911 owner can make would be to change to the new 'Barrier' hose which resists this weeping of refrigerant.

f. Thermostat; The second switch on dash, this one has a small hollow tube containing R-12, that senses the temperature of the Evaporator. coil and shuts off the Compressor if it gets below a predetermined setting. After a half-hour of freeway driving, this switch should be turned back a quarter turn to prevent the coil from icing up, especially at lower blower speeds.

g. Blower Switch; Usually a three speed switch that controls the Blower Speed and the Clutch on the Compressor too. When first you start up the car, switch to high and open a window to flush the hot air out then turn the blower to a comfortable level (refer to above).

h. Clutch: The electromagnetic connection between the belt and the Compressor. A series of windings in the field are energized when the a/c is engaged causing the hub (which is secured to the Compressor shaft) to be attracted to the pulley. This is a metal to metal connection and will eventually wear out especially if allowed to slip.

To 'AIR or not to 'Air...

Why the heck not ! Unless you use your car for a full timey racer, why not be as comfortable in your Porsche as you are in your Rabbit ? This is a car you probably only use in the summer anyway, why not enjoy it ?

Can it work?

When installed correctly and maintained adequately the a/c in your Porsche is as efficient as any other car, and can be even more so !

What are the main Troubles?

Essentially the biggest problem is the way the car is laid out that causes the Porsche to have 8 or 10 times more hose than a real car. The trouble being that a/c hose has always been made to purposely leak through tiny pin holes along it's entire length. Such a small amount as not to measured but nevertheless leaking. The new Barrier Hose should eliminate this drawback. The other problem has to be that no manufacturer ever seemed to have enough Condenser on the car for the Hottest Days.

What about winter storage?

While I can't guarantee it, I'm certain that if you use your a/c once a week or two for just ten minutes you will maintain the moisture in the seal enough to ensure a long life. So make a calendar, and each Sat go out and start the car, let it run for ten minutes, with the a/c on. Except when it's below Freezing outside unless the garage is heated. Silly me !

Should I remove the belt off season?

Definitely not, for doing so would not let you be able to exercise the a/c once a week. Besides the belt uses nearly zero h-p when the a/c is idling.

What size belt does my a/c take?

A factory 911 from '71 through '83 will use a Dayco 17430 or a 17435 if you don't have the strength to put the short one on. Using the shorter one will give you more room to the right of the Compressor. Non-factory a/c's take a variety of Special belts, but Dianna at (714) 634-9184 will know just which belt you need and have it in stock. All these belts are going to a little hard to install, mainly because there isn't much room for adjustment, so the belt must be tight at first or the Compressor can't move enough to make it tight. To install a Factory belt, take all three bolts out, back the adjustment nut all the way left, slip the new belt over the lower pulley and lift the Compressor as far as possible towards the center, place the belt in the Compressor groove and let the Compressor down and back into place. Start the three bolts again finger tight, then tighten the adjustment nut until the belt is very tight, tighten three bolts and you're done. Easy, eh !! On any a/c the belt must be very, very tight or it's gonna be noisy. For those out there with an add-on a/c, screw in two 3/8 nc x 1" capscrews into the Compressor in the holes closest to the head, now remove the two capscrews going into the Compressor through the bracket from the bottom. Now swing the pump around so the belt is loose. Replace the belt, then slip a long pry bar between those two capscrews you installed and pry the pump back with one hand and start the two bolts with the other. Simple, huh?

Will any York Comprssor work on any Porsche?

The answer is certainly a definite NO. There are 6 different Yorks used on various Porsches and these really should not be interchanged. For instance most add-on units were smart enough to use a 6 cu. in. York. DPD used a 6 in. Mini-York. VPC used a full size 6 in. York and the Factory from 1971 through '83 used a Monster 10 cu. in. York. A lot of factory a/c in domestic car will also use 10 in comp. but the problem that we see is when someone takes their Porsche to a shop and the replace a 6 in. with a 10 in. and then the clutch and/or the belt won't hold. Make sure that you get the same size compressor that you had in the first place. Of course a 6 in. pump will work just fine on a Factory system.

What about servicing the engine with a/c?

I realize that having that Compressor sitting there in the way can be a pain, but on most models, just three 8 mm bolts are all that hold the lump in your way. Make yourself a 18" square Pad of heavy plastic covered with an old blanket. Place this on the fender, remove the three belt adjusting bolts, and swing the Compressor out onto the fender. Wa-la

Can I mix and match belts?

There are two different belt angles used on the Porsche a/c's and it is not wise to mix them. If you have a 37 degree crank pulley, don't use a 60 degree Clutch pulley. Take a good look or hold a belt into the groove, if the walls of the belt don't contact the sides of the pulley, it won't work because all belts drive from the wall.

How much freon does my a/c hold?

All non-factory a/c's in 911's will be satisfied with 28 oz. of R12. The factory a/c with a front Condenser and a double row rear Condenser will hold 39-42 oz. With only a rear Condenser it should take 34oz. The Important thing hear is not to put in any more freon that it takes to clear the Sight Glass on the Receiver/Drier. This MUST be checked with the deck lid CLOSED and the engine running at 2000 RPM for a minute minimum. Putting in more Freon than is necessary will do no good and only serve to make higher head pressure, more heat and damage your parts.

Any Special treatment for the Porsche a/c?

Nothing, nada none EXCEPT Keep the engine lid CLOSED when using the A/C !!

Why does my engine almost stall when the a/c kicks on?

Because one of two reasons or both of them, You have too much Freon in your a/c or because you have a factory a/c with the Truck Compressorressor on it. This 10 monster was used only on trucks or large cars when Porsche chose it to replace their 5 incher. If you want a smooth engaging, smooth running, compact, lightweight Compressor then the only choice is a Seiko- Seiki True Rotary Vane Compressor. When this Compressor engages on the highway, you won't be able to detect it! A lot of a/c mechanics claim, even swear that the Sanden is a rotary, and while they do indeed make one, you'll probably NEVER see one. If it says 507 or 709 or 508 or 510 or 505 it is a swash plate with 5 or 7 pistons and 5-7-8-or 10 cu. in. displacement. York also made a Rotary for a short while but no longer does. Nippondenso is also experimenting with Rotary as is Panasonic.

How do I read the Sight Glass on my Factory A/C?

Whereas most sight glasses are on the top of the Receiver/Drier, Porsche put theirs on the side. What you are looking at is actually the level of the Freon in the Drier. The little white ball in there is to let you know that the level is higher than the glass so the ball will float and be at the top of the window. As soon as the ball floats to the top of the glass, STOP adding Freon. Of course the car must be running at 2000 rpm, HOOD SHUT, a/c on to read this.

My Factory A/C seems to use an awful lot of Freon?

Over the years I have found this to be true and I have yet to be able to say for sure where it goes, but I firmly believe that the hose is to blame. I think that their hose is just more porous than the rest. Another sure leak with the York Compressor on a Factory a/c is the joint at the head of the Compressor Porsche insisted that York use Two gaskets, an o-ring and the composition gasket it used before there was an o-ring. This is WRONG with a capital W. If you have a '71 to '83 with a big York on it, take hold of the hoses where they leave the Compressor, if they move up and down, then the gasket under the plate securing the fitting to the head is broken and should be replaced. NOW use ONLY an o-ring here, a special square cut o-ring, and oil it good. They should be tight as this is NOT a movably fitting.

MY dash is Broken!  What can I do?

Well if you have an early 911 or 912 and the plastic under dash panel is broken, have NO FEAR !!! We have come up with an underdash bezel that replaces four brands of a/c made for the Porsche.

What is that little TUBE coming from the thermostat?

That is a Copper tube filled with Freon that sticks into the Evaporator. coil and senses the temperature. At a predetermined temp., it opens the circuit to the Clutch which allows the temp to rise to another predetermined temp (usually +8 or 10 degrees) then it closes the circuit again. This probe must have good contact with the fins of the coil or it will allow the coil to freeze up and that is not good even if it sounds good. If the coil freezes, the air must go around it and the air comes out warm instead of cold. So if you notice that your a/c works at low speed (car speed) and then quits cooling after a half hour or so, check this . Handle the probe very gently and polish the end with crocus cloth before inserting into a new location in the coil if it was loose. The probe should go in about 4" and at an angle to get between the coils.

What brand of A/C do I have in my 911?

A Factory a/c from '69 to '76 has three thin louvers on either side of the ash tray and the temp switch. is on the left. The word Behr is on the Evaporator. in the heater box.

A VPC has two slightly larger louvers on either side of the ash tray and both of it's switches are mounted to the right of the ash tray. Their logo is CCCCOOL

A DPD has the same two louver set up as VPC, the switches straddle the ash tray but with the temp. switch. on the right. Logo is simple--DPD

Coolaire has a solid Plastic face that runs the WIDTH of the dash and the ash-tray mounts below this. There are two large flex-tubes that jut out from the firewall and carry the air to the dash. The controls are directly below the steering column. Also has a large plastic bump under the hood.

Since '77 all the switches are mounted in the console so it's a little harder to tell them apart but you will find a logo or brand tag somewhere on the unit.

There really is no clear cut Best one, each has it's own plus's and drawbacks and each can be made to work as well as the rest. I'm sorry to say that the '77 was the worst a/c Porsche ever put on the street. Only one small condenser and no vent under the dash made this one sorry unit, but not to despair it can be updated.

What Vent are you Talking About?

Well, believe it or not, there is a small plastic deflecter covering a small vent situated just above and forward of the console in the '78 through the present. Not many owners have ever felt anything coming from this vent but it can be opened up and we have an adapter that can greatly increase the amout of air that gets into the cabin to cool you off.

How can I make my a/c colder?

If, after making sure the a/c is full, you don't think it is cold enough one alternative you have is to add more condenser area to the system. A good way to measure this is : Place the car in the shade, engine lid closed, place an accurate, sensitive thermometer through the louver in the center of the car. If your 911 has a front Condenser, check now to see if the fan is working, by holding your hand under the Condenser while the a/c is on. You should feel a tiny whisper of air coming through the Condenser, it doesn't get any better than this, but if no air is felt, get this fixed now.

Turn the a/c blower on to low, turn the thermostat to max, raise the RPM to 2000 and hold it for 5 minutes. The temperature of the air at the discharge should be between 36 and 42 if the a/c is working at it's peak. If the clutch begins to cycle (click on, pause, then click back on) before it reaches this temp, it may be that you could adjust the thermostat but I would leave this to a pro.. If your 911 is a late '76, a '77, or an early '78 and has only one condenser on the deck lid you may not be able to attain those temps and will surely need to add more Condenser to make yours work that well. For those with non-factory air, your Compressor is a 6 model, (at least it should be) so the system doesn't need as much Condenser as Factory air but you could improve your a/c by going with a little bigger Compressor and adding more Condenser. Another note, check to be sure that the heater levers have completely closed off the heater ducts to the inside of the car. If any heat is let into the interior it will fight the a/c and win!! Even the best a/c can't overcome a weak heater!!!

A word about Fuses, circuit breakers and relays!!

For several years, the factory made the same mistake on every car with a/c. When they wired the fuse board on the '76 to about '79, they wired the Evaporator. circuit together with the Front Condenser. Fan circuit. So that all the elec. load was through ONE fuse. Well since those ceramic fuses can hardly handle 20 amps. the load of 30 or 35 amps. was way too much for them. The connectors turn blue, get loose and will actually melt. Check your car and if the second fuse from the back of the fuse board is distorted see if the red/white wire is connected with the red/yellow wire. If it is, separate them and connect one of them to the next fuse which should be empty. A very good substitute for these fuses or any fuse that seems to be overloaded (that is , gets hot ) is a circuit breaker. A c.b. can be wired with a tighter connection, won't blow at the slightest provocation, and will reset itself automatically.

Most all of these a/c's will have a Relay somewhere in the circuit mainly to protect the delicate switches from the high loads of the motors. Most over looked is the Factory relay located in the heater box next to the Evaporator.

What about TURBOS !!!!!!

When the Factory put air on all the turbos that came here they did some awful stuff to them starting in '79 with the Mini-York that stood up tall and shook like Tina Turner trying to get off that engine! Well, if there was ever an application that CRIED out for a Rotary, this is it !! Then if you add a fan to the bottom of the Condenser. on the lid, you can actually enjoy the car and the air !!!!

What about changing to r134A ?????

More about this a little later.............

Back to Previous Page


Comments and Suggestions:
Randy Comments: My 2002 911 Turbo - the a.c. blower motor runs and as you turn it up you can hear it increase in speed - but no air is blowing out the vents ??
August 14, 2017
  Followup from the Pelican Staff: Possible the cage on blower is broken and not spinning with motor. - Nick at Pelican Parts  
Mike Comments: What is the low side psi and what is the high side psi for a.c. on '02 911
June 2, 2017
  Followup from the Pelican Staff: That depends on the charge level and ambient temp. assume 30 low and 200 high for about 70 degree and fully-charged. - Nick at Pelican Parts  
Porsche Comments: 2002 c2 , AC seems to flucuate from cold to cool . I have to lower temp gauge much lower than previously .
March 31, 2017
  Followup from the Pelican Staff: Have the a/c pressures checked, it could just be low on refrigerant, if it is low, make sure to check the evaporator, that is a common failure point. - Casey at Pelican Parts  
DeeKid Comments: I have a 2000 Porsche 911 Carrera and when I use the A/C I get a high pitched whining sound upon startup. It sounds like the noise is coming from inside of the dash or near the battery area. It doesn't happen when I start up with the A/C button in the off position. It does not occur when I use the heater. I usually start the A/C after I drive so that the sound will not be noticeable to other people. The A/C works well. It weird that it occurs only after startup. To me it sounds like something is releasing pressure. It is not the blower fan, I have no problem with that no any noise. Could this be problem with too much refrigerant? Any ideas???
March 6, 2017
  Followup from the Pelican Staff: This is likely the sound of the refrigerant moving through system. I would check system pressure to see if there is an issue. - Nick at Pelican Parts  
VZ935 Comments: Does anyone have any solid information on a factory 69 A/C set up? Mine was removed with the exception of the blower which is in the "smugglers box". I have been able to determine the 69's did not have the blower up front in the suspension pan area.
I need to determine where the hoses ran for the A/C, under the car or through the rockers, etc. and any other technical info.
Apreciated, Van
September 29, 2016
  Followup from the Pelican Staff: I do not.
I opened a post in our forums. A Pelican community member may be able to answer your question.

Give The Pelican Parts parts specialists a call at 1-888-280-7799. They can figure out what part or repair kit you need.

- Nick at Pelican Parts
kitesurfer2 Comments: Please can you tell me how much oil to put in my 1978 930 factory aircon when recharging with R12?
Many thanks
Paul Lodey
August 12, 2016
  Followup from the Pelican Staff: I don't have info that far back. It also depends on what you replaced or repaired. Give The Pelican Parts parts specialists a call at 1-888-280-7799. They may have the info. - Nick at Pelican Parts  
Ron Comments: 2000, 911, A/C fan getting noisy, can these be rebuilt, or are bearings not replaceable, or in stock. Wouldn't be fan motor?
July 1, 2016
  Followup from the Pelican Staff: You'll need to replace the entire unit.

Give The Pelican Parts parts specialists a call at 1-888-280-7799. They can figure out what part or repair kit you need.
- Nick at Pelican Parts
Dick Comments: Do you still sell the under dash A/C bezels to replace broken units found on early model 911's? I have a '76 911S.
April 8, 2016
  Followup from the Pelican Staff: Pelican Parts can get them. I’m not the best with part numbers.

Give our parts specialists a call at 1-888-280-7799. They can figure out what part or repair kit you need. - Nick at Pelican Parts
cnas Comments: where is the sight glass/ reciever located for the ac system on 1986 911
June 12, 2015
  Followup from the Pelican Staff: Should be on the receiver / dryer. - Nick at Pelican Parts  
johnhedge Comments: My Porsche shop tells me that my aftermarket a/c stalls my 964 when I turn it on due to a lack of engine management. Can I rectify this?
November 14, 2014
  Followup from the Pelican Staff: That would be a question for the aftermarket ac manufacturer. I would think you could add an idle switch, to raise idle. - Nick at Pelican Parts  
PreA Comments: Hi: Looking for a compressor belt for '73 VPC York unit. Noticed a comment on: Dianna at 714 634-9184 "will know just which belt" for dealer installed systems. With phone number no longer in service... any idea on how I can obtain the correct V belt?

November 9, 2014
  Followup from the Pelican Staff: Give our parts specialists a call at 1-888-280-7799 and they can help figure out which part or repair kit you need.
- Nick at Pelican Parts
Pap Comments: I have a 1982 911 SC and the drivers side vent next to the door is throwing out hot air continuously. I have tried switching things on/off, adjusting dials but cannot get it stop producing a constant flow of hot air from this one place.

Any suggestions as to what may be causing this?
October 31, 2014
  Followup from the Pelican Staff: The flap for the vent may be faulty. - Nick at Pelican Parts  
Curlie Comments: Had freon added to my 81 930 Turbo. It worked great the first day, but after a road trip it stop blowing cold air or any air at all. Could this be a problem with the switch on the console?
August 10, 2014
  Followup from the Pelican Staff: COuld be the switch, the blower motor or the resistor. - Nick at Pelican Parts  
Black Baron Comments: We are on a road trip and have a noisy a/c pump, Can you dismantle the clutch assembly to disconnect the drive and continue the journey?
June 23, 2014
  Followup from the Pelican Staff: I don't know what kind of car you have. BUT - on some vehicles, you could remove the clutch and run a shorter belt. - Nick at Pelican Parts  
Marco Comments: Hi Nick, no, the defroster is not on. Everything is off when I turn the car off, but when I start it up again, the fan will always turn on automatically. AC is off, as I turned it off - but the fan will always be on each start.
June 13, 2014
  Followup from the Pelican Staff: There may be an issue with a temp sensor, commanding the fan on. - Nick at Pelican Parts  
Marco Comments: I have a 1999 C2 Cabrio. Each time i start the car, the AC is on, so I always have to turn it of, even though I it is off when I turn the car off. Any particular reason or fix for this?
June 12, 2014
  Followup from the Pelican Staff: Do you have defroster selected? - Nick at Pelican Parts  
airsea Comments: my 2009 Porsche 911 a/c is blowing air but not cold. Has there been any reported fuse or Freon problems with this vehicle?
April 23, 2014
  Followup from the Pelican Staff: I would assume you have a refrigerant leak. I would have the system leak tested. - Nick at Pelican Parts  
chuck Comments: Sorry forgot to mention stalling is when its comming back to midle from driving Please help if u can
March 23, 2014
  Followup from the Pelican Staff: Could have the wrong jets in it. - Nick at Pelican Parts  
Chuck Comments: Ps Just had carbs rebuilt professionally and engine has less than 100 hours on it love car just no fun to drive in Miami beach hot hot!!
March 23, 2014
  Followup from the Pelican Staff: Could have the wrong jets in it. - Nick at Pelican Parts  
chuck Comments: 1969 911t ac when on stalls motor alot and since installation rpm s stick when shifting gears
March 23, 2014
  Followup from the Pelican Staff: Is the compressor in good shape? is it binding? - Nick at Pelican Parts  
wwest Comments: Good enough for a Tech Note...?

1988 Carrera Special Edition.

I have long been of the firm belief, and remain so, that refrigerant
leakage in our Porsche's is the result of a design flaw on the part of

Many naysayers will chime in and attempt to convince you that
the problem lies solely with the use of non-barrier hoses. But many
other marques of this era made use of these very same non-barrier
hoses and yet hold their refrigerant charge inatct for decade after

So what, then...?

Inadvertent over-pressurization, high side pressurization well beyond the 350-450 PSI that appears to be an acceptable high end pressure for A/C systems of this era.

Why, how....?

Many systems of this era used a HPRV BOV, a vent to atmosphere
pressure relief valve ***1 should the high side pressure exceed the normal pressure range. In the alternative some systems of this era used a high side pressure sensing switch to disable the compressor clutch once system pressures reached 350 PSI.

Some even used both...

***1. Yes, R-12 VENT-TO-ATMOSPHERE....!!! Even in my 1992 Ford AeroStar...

Why make use of both provided the pressure switch prevents the
compressor from forcing the high side pressure from being

Because there is MORE to the equation.

Suppose the compressor has just driven the pressure to the limit, 350 PSI, but now you switch off the ignition...?? Now you have just
disabled the airflow that was cooling the rear lid and front lip
condensers, keeping the high side pressure "in check", against the
CONSTANT engine/exhaust radiant heating, as it were. Loss of cooling, now NOTHING to compensate, overcome engine/exhaust RADIANT heating of the rear lid condenser, the high side pressure will undoubtedly begin to rise.***2

More to the equation.....engine and exhaust manifold HEAT.

Even without the rea lid condenser being problematic Porsche engineers recognized the problem of engine compartment HEAT in the 964 and 993 series, and yes, even in our 996/997 cars.

With the 964 came a new design aspect that helped to prevent the
engine compartment HEAT from rising too high in certain conditions.
With extended idling, say iwith consistent, prolonged, rush hour stop and go driving, if the engine compartment temperature, convection + radiant, exceeded 70C the cabin heater blower would be powered on to help "wick" the exhaust manifold HEAT away from rising up through the engine cooling fins/vanes.

The new design aspect also included an "after-run" engine compartment cooling capability. If, as you switched off the ignition, the engine compartment temperature was above 30C then a 15 minute time delay circuit was "armed". Now, for the next 15 minutes, if the engine compartment temperature continued to rise and reached 70C the cabin heater blower/fan would be powered. Again, to wick away the exhaust manifold heat and discharge it into the rear wheelwells.

***2. For purposes of this dissertation lets make the following assumption, which is not exactlly a rare situation, circumstance.

Assume that as we switch off the ignition the A/C evaporator core is already at ~33F, thus the TXV is mostly closed, the R/D is filled with seevral ounces of liquid refrigerant.

And now with no air being circulated through the evaporator cooling fins/vanes it might take many minutes for the R/D's
liquid refrigerant to be "exhausted" and then for the high side and
low side to begin equalize. More than 20 minutes according to Charlie at Griffiths.

Sidebar: Google..

Bob Tindel cooling

Solution for leaking non-barrier hoses.

Tape and insulate a thermistor to the metal pipe as it enters the rear lid condenser. Use the thermistor value to discern if/when the high side pressure exceeds 300 PSI. Once 300 PSI is sensed then power the cabin heater blower/fan. Should the sensor indicate 350 PSI disable the compressor clutch circuit. Ignition on or off, POWER the cabin heater blower/fan as long as, whenever, the sensor value indicates 300 PSI.

This may not only prevent the loss of refrigerant on a 1 or 2 year
cycle, it might well raise the overall A/C system performance to a more adequate level.

With the engine idling at ~800 RPM I meaured ~100 Ft/m airflow at the center/top of the rear grille, with the cabin heater blower powered it went to ~200 Ft/m. Single point measurement, no attempt to calculate overall inlet airflow.

Thermistor alternative: The EPA requires the use of a high side pressure switch when converting an R-12 refrigerant A/C system to the use of R134a. This is because R-134a, absent some sort of control, wil operate with pressures well above your system's design specifications. I recommend using the Red Dot trinary pressure switch. First, because it will limit the operating high side pressure within the limits of R12***3.

Second, the 3rd function of the Red Dot trinary pressure switch can be used to control the cabin heater fan. And the front lip condenser fan if you wish.

***3. An R-134a trinary or binary pressure switch will allow the high side pressure to rise ABOVE the system design specifications whereas the Red Dot switch will not.
August 6, 2013
  Followup from the Pelican Staff: Wow, thanks for taking the time to write and share this this with us. This is certainly tech note worthy. - Nick at Pelican Parts  
Botoo Comments: On my 1990 911 C2, the air conditioner only seems to work when the temperature dial is on the very coldest setting. On all other settings of temp. control, hot air comes out of the vents. Can anyone help me diagnose what is wrong?
July 25, 2013
  Followup from the Pelican Staff: Your blend door may not be working properly. It could be dirty, stuck or falling apart. See this tech article for some FAQs

/techarticles/mult_AC_faq/Mult_AC_faq.htm - Nick at Pelican Parts
Peter Comments: I have a 1985 911 Targa, the ac compressor is working, but the air is blowing warm air. Is it possible to convert to the new ac coolant inexpensively? Or should I get it charge by an ac shop and not even bother with it? thanks.
August 13, 2012
  Followup from the Pelican Staff: I would take it to s shop. You likely have a low charge from a leak. They can find the leak, repair it, then retrofit the system. - Nick at Pelican Parts  
micko76 Comments: i've got a 1976 912E with A VPC air conditioned. I've got the plastic under the dash broken in the left side.. What can i do?
May 18, 2012
  Followup from the Pelican Staff: The vents are replaceable. If this is what you're referring to. Give our parts specialists a call at 1-888-280-7799. They can help you find the right part.
- Nick at Pelican Parts
mark Comments: I have a bit of a strange problem with the aircon in my 964 in that it only works when the car is actually moving !
I am living in Malaysia, so hot most/all of the time, so sitting in traffic with no aircon is a bit stressful as you can imagine.
Having swapped the control box for one which is known to be working correctly in another 964, I suspect that one of the sensors which feed the box is not working correctly. But which one ?

When sitting in traffic, the clutch on the compressor chatters ... so switches on briefly, then off again, so something somewhere is cutting the power to it.

Any thoughts what can be doing this ?

thanks, Mark
March 17, 2012
  Followup from the Pelican Staff: Have you checked cooling fan operation? If now working, when stopped your A/C will not cool properly. - Nick at Pelican Parts  
ellen Comments: What are the two parralel tubes located on the undercarraiage of the 2003 prosche 911 Carrera 4
November 11, 2011
  Followup from the Pelican Staff: I'm guessing that these are the water pipes running to the front radiators. - Wayne at Pelican Parts  
ellen Comments: Where is the vent tube for the A/c system on 2003 prosche 911
November 11, 2011
  Followup from the Pelican Staff: Sorry, I'm not exactly sure what you mean by "vent tube"? - Wayne at Pelican Parts  
Cheap-a-doublesnakes Comments: The fan is broken in the trunk up front. Am I correct in assuming that if this isn't working to at least help the system get rid of the heat, then I am not going to get cold air inside? If all else looks fine, will repairing/replacing this get me better AC?
July 5, 2011
  Followup from the Pelican Staff: The fan does have to work for proper cooling. I would repair it, your A/C should improve. - Nick at Pelican Parts  
lamar Comments: My crankshaft pulley damper has crackes ,how can I replace
it. My car is a 912e this damper is a large round rubber
part in the middle of the pulley that runs the air pump and
air conditioning
April 19, 2011
  Followup from the Pelican Staff: It should have small bolts that hold it to a flange on the crankshaft. Remove them, then the pulley comes off. - Nick at Pelican Parts  
Elmer Comments: I just change my a/c expansion valve on my 86 911 carrera, I wonder if any one know who sell a 134a retrofit o ring kit so I could change all my o rings before I charge the system with new freon.
October 23, 2010
  Followup from the Pelican Staff: Give our sales dept a call in sales at 1-888-280-7799 and he should be able to assist you with this. - Wayne at Pelican Parts  
GL Comments: Have a 1987 911 Carrera, which one is the low pressure connection, the lower plug facing the rear section of the compressor or the higher plug towards thew top front of the comnpressor? Thanks for the help
June 21, 2010
  Followup from the Pelican Staff: It depends slightly on the compressor model, here are two links that should help you out:

/techarticles/911_AC_upgrade/911_AC_Recharge.htm - Wayne at Pelican Parts
Jay Comments: Hi,
I am installing the air con evaporator and blower unit in the footwell of my 86 930 but I can't find any digrams or photos of the mounting brackets for the evaporator unit. Do you know where I could find a picture or digram of the mounting of it?
Many thanks
June 1, 2010
  Followup from the Pelican Staff: You might want to try the Porsche diagrams located here: - Wayne at Pelican Parts  
coma Comments: In Tech Articles - Porsche 911 Conditioning Frequently Asked Questions someone mentioned that they have come up with a A/C under dash bezel that can replace broken/defective original pieces see below.
Where can I find these replacement bezels?


MY dash is Broken! What can I do?
Well if you have an early 911 or 912 and the plastic under dash panel is broken, have NO FEAR !!! We have come up with an underdash bezel that replaces four brands of a/c made for the Porsche.
January 24, 2010
  Followup from the Pelican Staff: The vents are replaceable. If this is what you're referring to. Give our parts specialists a call at 1-888-280-7799. They can help you find the right part. - Nick at Pelican Parts  

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