2 hours ago, bubib5 said:

If you are still in Croatia i do know a few guys that might be able to help you out!

Thank you so much Sir for the offer...we are travelling home on Friday early morning and they are forecasting max 24-25 so should be OK until we arrive. Will still try to stop for 2x 30 minutes break and try to reset the flaps. I think one of the flaps is still a problem and long way can cause icing on the AC so the performance drops. But with 2 breaks, it should melt down by then. Poor that we need to solve such a thing on a 40k$+ car

1 hour ago, Ber31inger said:

Thank you so much Sir for the offer...we are travelling home on Friday early morning and they are forecasting max 24-25 so should be OK until we arrive. Will still try to stop for 2x 30 minutes break and try to reset the flaps. I think one of the flaps is still a problem and long way can cause icing on the AC so the performance drops. But with 2 breaks, it should melt down by then. Poor that we need to solve such a thing on a 40k$+ car

No worries, if the need should arrise, i do have 2 trusted people in Zagreb, Croatia, so just shout!

On 22/08/2021 at 22:13, bubib5 said:

No worries, if the need should arrise, i do have 2 trusted people in Zagreb, Croatia, so just shout!

 

Hello Ber31linger, I have a 100% similar problem on my Octavia 3 and I am wondering if you managed to solve the "mystery"?

Thanks a lot!  

Just now, Florin1528 said:

 

Hello Ber31linger, I have a 100% similar problem on my Octavia 3 and I am wondering if you managed to solve the "mystery"?

Thanks a lot!  

Hi Florin, unfortunately no...and since summer was over that time I had no longer trips in hot days, I did not really focus on it anymore....but I would need to do now, as summer is again approaching. I tried to reset the flaps several times, but it did not help unfortunately. Let me know if you find out something please.

47 minutes ago, Ber31inger said:

Hi Florin, unfortunately no...and since summer was over that time I had no longer trips in hot days, I did not really focus on it anymore....but I would need to do now, as summer is again approaching. I tried to reset the flaps several times, but it did not help unfortunately. Let me know if you find out something please.

Thanks for you quick response mate  . I am currently investigating the problem and promise to come back if succeed (fingers crossed). But if you'll find first please let me know  

 

Thanks

Florin

15 minutes ago, Florin1528 said:

Thanks for you quick response mate  . I am currently investigating the problem and promise to come back if succeed (fingers crossed). But if you'll find first please let me know  

 

Thanks

Florin

Absolutely - will do! Divide and conquer 

 

Sorry for "stealing" this topic but, as I understood from the skoda dealership when my factory compressor failed, the ones fitted to the MKIII superb do not use a clutch but a valve system. So, in principle, the compressor is always running but only "working" when solicited. Does this mean it would be best (or at least not harmful) to leave the A/C on auto all the time and let it do what it needs when it needs it? I've always heard that A/C compressors should be used regularly, to prevent seals from drying/leaking.

Cheers!

2 minutes ago, pcspinheiro said:

Sorry for "stealing" this topic but, as I understood from the skoda dealership when my factory compressor failed, the ones fitted to the MKIII superb do not use a clutch but a valve system. So, in principle, the compressor is always running but only "working" when solicited. Does this mean it would be best (or at least not harmful) to leave the A/C on auto all the time and let it do what it needs when it needs it? I've always heard that A/C compressors should be used regularly, to prevent seals from drying/leaking.

Cheers!

Anyone familiar with the workings of an air con system both mechanically and electronically will tell you, leave the AC on 100% of the time. AC is not a air cooling function but a air conditioning function. It has many purposes, it drys the air, removes microscopic bits of anything in the air, cools the air, then it passes through the heater to heat it to the required temperature. These systems are made to be left on and not work at 100% all of the time, the valve is there to make the system only work when needed and at any percentage of power in between.

The N280 valve has a minimum opening which ensures that even when switched off a small proportion of the refrigerant still circulates, so no worries about seals.

 

 

 

 

 

 

Edited 20 May, 20224 yr by Pete_Ex-Wino
Unnecessarily pedantic material removed

1 hour ago, Pete_Ex-Wino said:

All it does is cool the air.

 

Humidity reduction is a simple side-effect of that. 

Pollen filter removes particulates before they get to the evaporator, otherwise the evaporator will soon clog with debris.

 

The N280 valve has a minimum opening which ensures that even when switched off a small proportion of the refrigerant still circulates, so no worries about seals.

Sorry but i completely disagree with you.

 

Humidity reduction isnt a side effect, the system is perfectly designed to create a near frozen evaporator which yes cools the air but also freezes any moisture in the air and allows it to drain, there is a lot of particles that are small enough to get through a pollen filter such as smells and fumes, these too are collected by the partially frozen evaporator and are allowed to drain away in the collected moisture as a solution. The evaporator wouldn't and shouldn't clog with any debris, were not talking leaves and stuff but microscopic bacteria and objects, as the evaporator cycles between frozen and slightly warm the frozen layer is melted away and allowed to drain under the car.

 

Anything to actually show the N280 behaves as you say because thats a new one on me?

1 hour ago, pcspinheiro said:

Does this mean it would be best (or at least not harmful) to leave the A/C on auto all the time and let it do what it needs when it needs it?

Yes. You'll get a more comfortable interior temperature, and fewer issues with things like condensation.

Just now, ApertureS said:

Sorry but i completely disagree with you.

Thought you might. Shame I didn't get my edit in before you bothered.

 

3 minutes ago, ApertureS said:

Anything to actually show the N280 behaves as you say because thats a new one on me?

The SSP I read on the N280 regulated systems says that a minimum of 4% circulation occurs, from memory.

Edited 20 May, 20224 yr by Pete_Ex-Wino

Pete ex Wino is correct, I also read it in the self study program.

 

VCDS also shows it in the compressor loading measuring block, granted its only a calculated and not a measured value but it shows some loading when the AC is switched off, it will also show full loading when AC is switched on to maximum but the shear plate is broken and the compressor is not even turning!!!

7 hours ago, ApertureS said:

Anyone familiar with the workings of an air con system both mechanically and electronically will tell you, leave the AC on 100% of the time

I am but I wouldn't so not "anyone" in the inclusive sense.

 

Someone familiar with the workings of an air con system both mechanically and electronically may tell you, leave the AC on 100% of the time

 

 

On 20/05/2022 at 12:11, Ber31inger said:

Absolutely - will do! Divide and conquer 

 

Hello Ber31inger,

 

Promised to come back with some updates as I found out something   

 

After several tests and reading values using VCDS and OB11 all the values appeared to be OK except the ones below:

 

1. Pressure in BAR (while running at idle) was low: 10 BAR ; 10.8 BAR (maximum recorded)  - outside temperature when doing the test + 25°C

2. Left, Right and Foot temp sensors where not showing the same values (Left sensor had the lowest values- most probably because the Air Conditioning is going into the car from Left to Right- why I am saying this is because I switched the left and right sensors between them and same values => the sensors are OK)

3. Evaporator sensor was showing almost the same Celsius degrees as for the Left, Right and foot temp sensors - normally the evaporator sensor should record lower temperature like for this example: Temperature set on AUTO to 22°C, left,right and foot temp sensors should read 13-15°C while the evaporator 7°C (or even lower; close to 0).

 

Because of point #1 and #3, I realized that maybe I don't have sufficient refrigerant gas in the system and I went for a check. The outcome after this check was that I only had 150gr OUT OF 500gr - this might be the reason of low pressure and high evaporator value. 

After completely filling the air conditioning system the pressure when to 11.5 - 12.5 BAR and the evaporator value dropped to 3-5°C and the air conditioning is making much more cold and much faster than before. (I didn't had a long trip since refilling so I don't know if my old problems still persist or not)

 

PS: In the past I also had the symptom of auto-closing the flaps (no air coming through the vents) but that was solved by changing the cabin filter 

 

Hope this helps your investigation too 

 

Cheers,

Florin

How old is the car? Why do car ACs lose refrigerant gas like this? I believe it has become "normal" to repeatedly refill the car's AC with refrigerant, but house ACs usually go on for many years - even decades - without needing more refrigerant. This means there's a leak somewhere, since the gas isn't consumed during operation...

35 minutes ago, pcspinheiro said:

How old is the car? Why do car ACs lose refrigerant gas like this? I believe it has become "normal" to repeatedly refill the car's AC with refrigerant, but house ACs usually go on for many years - even decades - without needing more refrigerant. This means there's a leak somewhere, since the gas isn't consumed during operation...

House ac systems same as fridges are completely different from automotive ac systems.

The house systems have a hermetically sealed compressor and as such the system is completely sealed.

Vehicle system are different as the compressor is open and relies on shaft seals also the system has flexible hoses to allow for vibration/ movement etc all of which are prone to gas permeating out of the system . It is generally accepted that automobile ac systems can loose up to 10% of refrigerant annually .

Edited 20 June, 20223 yr by Kenny R

4 hours ago, pcspinheiro said:

How old is the car? Why do car ACs lose refrigerant gas like this? I believe it has become "normal" to repeatedly refill the car's AC with refrigerant, but house ACs usually go on for many years - even decades - without needing more refrigerant. This means there's a leak somewhere, since the gas isn't consumed during operation...

House AC systems never move and generally stay within a small temperature range. Whereas a car ranges from -10 up to well over 100 degrees. Cars have a lot more vibrations and rubber hoses which as much as they are 99% air tight, there is always a tiny leakage through rubber. 

 

That being said its not 'normal' to keep refilling a car AC system, maybe every 5/6 years or so is a safe number at maximum but it seems a lot of garages are completely incapable of working with AC systems let alone diagnosing and finding a leak, they all seem to think pressing the big green button on their machine after a leak test means the car is air tight when 99% of the time, its not. 

I agree, the car AC is under more extreme conditions, but leaking and needing refilling every year is definitely not normal. One problem with the "leak test" done by the AC filling machines is that they do this under vacuum, whereas the AC is under pressure the remaining 99.9999% of the time. I had this with my old Opel; the machine did the vacuum leak test and it was fine, because the vacuum was actually keeping whatever was wrong pulled tight against the leak, so it went on to fill with refrigerant. It was 100% gone the next day... 

A now retired pal who worked his life in the bottled gas supply industry told me that with any aircon system with rubber hoses or even O ring seals in dry break couplings it is not a question of if it will leak but how long before the refrigerant charge drops below the operating threshold.

 

Fridges and monobloc AC units are completely sealed the motor and pump within the big cylinder, pipes to the condensor & evaporator are solid steel or copper, split units that are charged during commissioning use flared couplings and unless they are badly made there will again be zero refrigerant losses.

 

the DIY ones being sold now with the precharged connection coils with dry break couplings will leak via the seals from day 1.

 

Car AC units with exposed pump seals, polymer flexible hoses and sealing washers will leak a significant quantity every year.

 

He told me that it is possible to have hoses and seals of a material with a molecular value such that leakage is negligible, they have to use them for HSE reasons but they would double the cost of a vehicle were they equipped with them.

It is ice for sure.  I am in India and its really hot and humid right now. 35C -40c temps and you get drenched in 15 min outside. 

After about 100km you need to turn the ac button off for 10min and you are good to go again as the ice melts off and the blower is able to blow enough air, notice the air volume drops and it get noisy if you up the blower.  Same thing used to happen in a VW Jetta I used to use before this maybe it's a Vw flaw.