Climate hose worn through - what's the correct procedure afterwards?

Hello,

Last Saturday, shortly after I started driving, I heard a brief, unusual hissing sound. When I glanced in the rearview mirror a moment later, there was a large white cloud. At that moment, I couldn't quite place it, but when no cold air came out of the vents for the next 2 kilometers, I realized what had happened – the air conditioning system had run out of refrigerant.

About two hours later, I started troubleshooting and discovered that the hose between the condenser and the compressor had worn through where it touched the dryer. I temporarily sealed it with electrical tape.

The hose needs to be replaced, and I'll also renew the dryer and the throttle. Additionally, the lower cooling fin on the condenser had come loose, so I'll replace that with a new one as well.

Now I have the following questions:
1. So wie ich es verstanden hab, muss man die O-Ringe an Verbindungen wechseln, die man einmal offen hatte. Is that correct?
What is the difference between a throttle and an expansion valve?
ELSA believes that if the refrigerant circuit was completely empty, the compressor needs to be removed, drained, and refilled with the correct amount of oil. I went directly to a dealership and an independent workshop, and both only wanted to flush the system and then refill it normally. Is that really sufficient?

Bye.
peace

pax wrote:

1. As I understand it, the O-rings on connections that have been opened once need to be replaced. Is that correct?

Okay!

pax wrote:

2. What is the difference between a throttle and an expansion valve?

I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.

pax wrote:

3. ELSA believes that if the refrigerant circuit was completely empty, the compressor must be removed, emptied, and filled with the appropriate amount of oil. Now, I went directly to the authorized dealer and a free workshop, and both only wanted to flush it and then refill the system normally. Is that really sufficient?

If the system was recently started or operating under very high pressure when this happened, it's best to follow the procedures outlined in ELSA.

Hello,

Thank you for the quick responses.
The hose burst approximately 30 seconds after starting the engine, with an outside temperature of 30°C (the car was parked in the sun). Unfortunately, I can't really estimate how much oil leaked out.

What specifications must the refrigerant oil meet? Volkswagen has its own very specific price expectations, so I would try to find an alternative product.

Bye.
peace

pax wrote:

Which specification must the refrigerant oil meet? VW has its own very specific price expectations, so I would try to find an alternative product.

"It's standard PAG oil, but even as an accessory from companies like Hella/Behr, it's quite expensive."

PAGE 46.
240-250 ml.
Liqui Moly product number 4083 is available for purchase. It costs approximately 10 euros for a 250ml can. I can provide the address of a retailer in Lübeck if needed.

Great, thank you. I was looking for that information .

This week I visited three car dealerships: two Volkswagen dealerships and one independent repair chain closely associated with the VW Group. At each place, I explained the situation, but no one could really tell me what the necessary amount of work would be or how much it would ultimately cost – which is a real shame.

Once again, thank you to the forum for sharing their knowledge.

Bye.
peace

Hello Pax,
The part numbers for the hose from parts suppliers (perhaps Stahlgruber or PV Automotive in Leipzig) are Vemo (Vierol AG) V-15-20-0022, and for the dryer, they are Waeco 8880700187 or Hella 8FT 351 192-381, depending on what they have in stock. You might want to consider using the Waeco dryer because it's a bit shorter and virtually eliminates the possibility of recurrence (see photo). Alternatively, you can attach a piece of heater pipe insulation as shown in the other picture.
The Waeco dryer comes with the O-rings. I'm certain of that. The hose should also typically come with a ring on the condenser side. Otherwise, the part number is 8E0 260 749 E and it costs approximately 50 cents.
Currently, there's a shortage of R134A refrigerant supply in our area.

Hello Steffen,

Thank you for the comprehensive research .

I sourced the capacitor, dryer (including O-rings), and expansion valve from AKS Dasis. The materials were relatively inexpensive. Since I'm not responsible to any customer but only to myself, I'm willing to try this experiment. Last year, I already installed a radiator from this manufacturer, which wasn't noticeably bad – so there's a certain level of trust.
Einen Klimaschlauch hab ich mir vorerst beim Schrotti gesichert, bin mir aber noch nicht sicher, ob ich den verbaue, oder doch in einen neuen investiere - vor allem weil er aus einem auf dem Hof rumstehenden Auto (Dreck, Feuchtigkeit) stammt und mir die Anschlüsse nicht 100% gefallen (siehe Anhang). Sind denn ausschliesslich die O-Ringe für die Dichtheit verantwortlich, oder auch dieser angefaste Bereich im Bild, der ja leider schon etwas narbig ist? I also noticed this at the junkyard – and Steffen's pictures confirm it again – that it seems to be typical to find hoses with attached fittings.

Okay, I'll start by removing the bumper and see if the Dacia parts fit mechanically.

Bye.
peace

Once you've assembled it, you'll be able to see how long the Dehumidifier is. If the hose still rubs against the dehumidifier, you can still use heating insulation as a solution.

It seems like this is a common issue with the Passat. After reading this post, I checked mine today and quickly added a piece of heating pipe insulation over the already worn-out hose. Without air conditioning in this weather, it wouldn't be much fun...


Thank you.

Holger.

Hello,

"Yes, it seems to be a general problem. The hoses at Schrotti's were also worn in the same spot. I was initially annoyed because I thought I had messed something up last year during the first timing belt replacement I did myself. But ultimately, it probably had been like that for longer, and I just hadn't looked at that specific area – which is still frustrating enough."

By the way, you can move the clamp on the dryer, where the retaining spring is attached, downwards. This will allow the hose to hang freely and prevent it from rubbing against the dryer.

Bye.
peace

Hello,

Here's a brief update. Yesterday, I tried to repair the air conditioner. Unfortunately, it was only partially successful.

First, I disconnected the service lines, removed the belt, and took out the compressor. I replaced the faulty hose and put the compressor back in – that was easy. Then it was time for the condenser. Luckily, I had already ordered a new one. The old one had a cooling tube detached. It turned out that four more tubes could be easily pushed out. That sub-task also went smoothly.

Then I wanted to replace the throttle body. The locking nut probably only moved about 5 degrees – and then it stopped. After three attempts, I realized that I should stop forcing it, because while you might have been able to get more rotation out of the nut, the resistance from the aluminum hexagon on the air conditioning hose would have led to its destruction.

As the final task, I had to replace the dryer. That almost broke me. First of all, you need a 30mm and a 32mm wrench, but the tools available only went up to 27mm - luckily, the hardware store still had what I needed.
The 30mm lug nut was just barely loose on the car, while the 32mm one was completely stuck. Because nothing else would budge on the vehicle, the dryer and the A/C line had to be removed. This required a second compressor disassembly. The A/C line was corroded and stuck to the guide pin on the compressor side. Before it could be loosened, another half hour of work was needed.

Jetzt gings samt Trockner mit angeschlossener Leitung zur Werkbank. Trockner eingespannt, Maulschlüssel angesetzt (32er Ringschlüssel bekommt man nicht über die Leitung) und zu zweit gedrückt und gezogen. Wir hätten es viell. geschafft, das Muttermaterial soweit zu schädigen, dass der Schlüssel einmal übergesprunge wäre - mehr war nicht drin. Danach haben wir die Überwurfmutter eingespannt - zum Glück ging das - und am Trocknergehäuse gedreht - nichts. Die erfolgreiche Idee war dann, über ein Holzbrett mit dem Hammer kräftige Schläge auf das Trocknergehäuse zu geben. Endlich passierte was. Es However, it was still necessary to use this violent method for an entire round until we could finally turn the locking nut with the key.

Highlight war dann, dass ich den Dichtring des Trockner-Kompressor-Schlauchs zwar vorsorglich bestellt habe und wir das vor Beginn der Arbeit anhand der Teilenummern auf der Rechnung auch nochmal sichergestellt hatten, allerdings war der Ring (nach Prüfung des eigentlich erforderlichen Durchmessers) nicht mit dabei. Naja, es gibt Tage, da verliert man und Tage, da gewinnen die Anderen ... I'll be having some more fun next week.

Okay, now let's move on to the important part: the questions that arise from this.
Which lubricant should be used on the fittings of the air conditioning system where aluminum components are involved?
Is there a kind of "rust remover" for aluminum oxide?
How can I loosen the fitting on the throttle body without damaging anything?
4. How do the professionals manage to install these fittings? If you want to make money doing this, you can't spend several hours on each one.

Bye.
peace

EDIT: It's done. All the exposed threads have been fitted with new gaskets. The throttle body has been replaced (I used rust remover for a week, which only stripped two threads, but at least I was able to unscrew it), aluminum shavings have been removed from the retaining nuts, and the A/C hoses have been routed so that nothing rubs anymore. It will be filled next week. Hopefully, everything will be leak-free then.I distributed a total of 45 ml of compressor oil to the new parts. Since the parts catalog didn't show anything related to seals or the drain screw for the compressor, I didn't empty and refill it.

"EDIT2: The system has now been running again for about 2 weeks. It was only evacuated for 20 minutes and then refilled without any flushing or other procedures. Whether that was right or wrong will be shown by the long-term test."