Datenlog Klimaanlage | Posts 16+

brezelmann01 wrote:

The HD value is consistently between 13 and 16 bar.

A pressure of 13-16 bar corresponds to a condensation temperature of 50-60°C. At an ambient air temperature of 30°C, the condensation temperature is therefore 20-30K higher.

I haven't personally measured anything on automotive air conditioning systems, but I have general knowledge of refrigeration technology. Typically, you aim for a temperature difference of about 10K. I don't think you'd deviate significantly from that rule of thumb in automotive applications. Therefore, I suspect a restriction in the airflow or the refrigerant circuit. This would mean that too little refrigerant is circulating, and the two heat exchangers are only being used partially. Could you check or feel the evaporator for testing? I suspect that only one corner will get cold, while the rest won't.

Typical bottlenecks could be clogged dryers or restrictions. Possibly swap them both at the same time.

PS: How much refrigerant was filled?

Greetings.
Guste.

vag-driver wrote:

It would be interesting to compare it to an A3 of the same build.

Offering an A3 8P from 2011. What specifications would you like to know? I'll do a test drive later using VCDS.

Best regards, Rainer.

Hello Rainer,
You may have logged in before, but I appreciate any data you provide!
In my opinion, the following data are ideal for climate diagnosis:

Vaporization temperature.
Power control valve, compressor.
Outdoor temperature.
Controlling the interior fan.
High pressure.
Temperature of male ejaculate.
Speed.

Ideally, this would happen while sitting in a car that's been nicely warmed up by the midday sun.

Thank you all for your help! By the way, the rear windows come tinted from the factory.

Regards,
Brezelmann01

Hi,

No problem, just: The temperature has dropped, and it's raining. If I forget, please remind me when it gets warm again.

Best regards, Rainer.

Hello!

If summer has returned in Switzerland, I would appreciate a log from a nicely warmed-up vehicle with a cold start.

LG
brezelmann01

I set a reminder.

Best regards, Rainer.

Hello Brezelmann,

Attached is the climate control log from my wife's A3. The car wasn't parked directly in the sun, but it was still warm inside. The outlet temperature at the evaporator decreased quite rapidly.

Best regards, Rainer.

Hi!

Excellent, thank you very much. I will carefully compare my logs .

Hello!

Okay, I've carefully reviewed Rainer's log. I'm surprised that, despite the high outside temperature, he's able to achieve an interior temperature with an evaporator temperature of 8.5°C and relatively relaxed control of the ventilation system? Apparently, there isn't even an effort to further reduce the vaporization temperature.

My system is trying to regulate and maintain the evaporator temperature at approximately 2°C, given the current outdoor temperatures.

Regards,
Brezelmann.

P.S.: I replaced the dryer and blew out the expansion valve. A replacement valve (once and never again!) didn't fit, so I had to put the old one back in. Since then, the cooling performance has been significantly better! R134a was almost completely present; in fact, it was still within the filling tolerance!

Hi!
Here's the log from today. The vehicle was parked in direct sunlight for hours and, as a result, was very hot. The evaporator temperature quickly rises to 2.5°C despite solar radiation and high fan speed.
I would therefore attribute the initial malfunction either to the dryer and/or to the expansion valve.

Maybe these logs will be helpful to someone else as well...

Regards,
brezelmann01