Air-conditioning service

[kwmax]

Hi can anybody advise me when is air-conditioning service required and is there a actual filter to replace  plus is there a requirement to drain and regas the system .jmax

[psycholist]

If the aircon isn't blowing as cold as it used to then it's worth trying a regas. I think some would recommend doing it every year or two, but that's one system where I'll wait till I see a drop in performance before doing anything (Don't do this with oil changes ). There is a filter dryer in the refrigerant line which should be replaced when new gas is put in AFAIK - this certainly should be done if the system has been left open to the atmosphere for a while as it will have already filled itself with water from the air and so won't be able to do it's job if small amounts of water get into the aircon lines later on. I'll probably regas my aircon for the first time this year as I suspect cooling is a bit weak when the weather is hot, but the car is over 6 years old now.

 

You can easily change the pollen filter yourself if that's the filter you're worried about. It's accessed from the passenger footwell, no tools needed. The activated charcoal one is what I have fitted as it's supposed to keep things smelling better - no complaints so far anyway, but I certainly can still smell smoke and farm effluent when the car takes in air contaminated with this.

 

The second light on the air recirculation button is supposed to be for automatic recirculation according to the manual it switches to recirculation automatically when it detects the air quality outside the car is poor, but I've never bothered messing with it to see if it works and they give no clues in the manual as to what they're monitoring the air for.

Edited 28 February, 2017 by psycholist

[kwmax]

Hi thanks reason for asking was car serviced at dealer they advised me of aircon srevice at £70  poss needed. drain system and regas.car has  no smell and works ok think they touting for business 4yr old 20000 miles 

[TheRobinK]

2 hours ago, psycholist said:

....according to the manual it switches to recirculation automatically when it detects the air quality outside the car is poor, but I've never bothered messing with it to see if it works and they give no clues in the manual as to what they're monitoring the air for.

 

Well driving around the fair County of Clare this week, I can absolutely and positively confirm that it does not monitor for cow **** smell.  

 

That said, I had the Superb parked in front of a BMW salesman recently. He was waffling about the status badge and "brand engagement" and I smelt absolutely nothing. SO, I can confirm that it monitors for, and filters out, both human and Bullsh1t and it does it Superbly.                              

[wokwon]

3 hours ago, psycholist said:

The second light on the air recirculation button is supposed to be for automatic recirculation according to the manual it switches to recirculation automatically when it detects the air quality outside the car is poor, but I've never bothered messing with it to see if it works and they give no clues in the manual as to what they're monitoring the air for.

 

 

As far as I know, it's an optical sensor similar to the way an optical smoke detector works.  So it would only detect dirty (i.e. less clear air).  I don't think it's the ethane etc type sensors as they tend to drift like hell and require frequent recalibration.

 

The recirc flap takes a good 5 seconds to close or open anyway (pull the glovebox out and watch it) so the sensor is of limited benefit and reacts slowly.  The dust/pollen filter is much more important.

[jafo]

It's good to run air con at least once a month for few minutes - for good lubrication of all the gaskets, etc.

[peterposh]

the  pollen filter gets filthy , makes you think twice about opening the window in traffic

[kwmax]

Thanks everybody but when does the system need regas at sevice interval or when you notice it not cooling car down ?

[psycholist]

I'd do it when I notice a drop in cooling performance, but there probably is an official service interval somewhere.

[James@RRG_Skoda_Rochdale]

Pollen filter is usually every 2 years 

 

an air con regas is recommended every 2 years 

[kwmax]

Thanks

[peterposh]

http://www.honestjohn.co.uk/faq/air-conditioning/

[safari hunter]

On 3/1/2017 at 00:49, jafo said:

It's good to run air con at least once a month for few minutes - for good lubrication of all the gaskets, etc.

For me it is OK to let it ON for the entire period of the year. Actually it is ON since I purchased the car 6 years ago.

Particle cabin filter should be replaced once a year or 15K km, while A/C circuit to be checked at every 2 years or 45K km not only for leaking detection but also to replace the compressor oil.

It is also advisable to replace the valves that seal the circuit at every 4-5 years, same as the tire valves.

[kwmax]

With respect can't see myself doing that. I run it every month in winter of course use it more in summer I ask the question what about new cars sat in show rooms for 3/4 months I bet they don't run a/c until it's moved 

[safari hunter]

With same appreciation pls see this quote: " A/C Fact: Your vehicles air conditioning system runs whenever you turn on the Defrost mode. It is designed to engage and act as a dehumidifier to remove the moisture from the air entering your vehicle to aid in removing moisture (fogging) from your windows. You will notice vehicles with working air conditioning that the side and back windows are always clear. Vehicles without air conditioning or needing A/C repairs will have steamed up side and back windows which continually need wiping to clear. If your A/C system is not working 100% at the end of the summer season and you think you will get it fixed next year, do not put it off or you will do damage to your compressor. Remember, when you turn on the Defrost Mode, the compressor is engaged. With a low refrigerant charge over the winter months, you’re not getting the refrigerant oil back to the compressor which is damaging it all winter season that will lead to costly repairs in the spring time."  source : http://autotechac.com/ac-facts-and-myths/

[kwmax]

Ok    so it advised to put the a/c on all the time 365 days a year if thats  the case why have on / off switch  regards 

[wokwon]

On 3/4/2017 at 09:05, kwmax said:

Ok    so it advised to put the a/c on all the time 365 days a year if thats  the case why have on / off switch  regards 

 

Because some people like to turn it off.  In older A-platform cars it used to be labelled "ECON" and when pressed lit up, showing that ECON (i.e. AC-off) was in operation.  This was a hint that the normal and default setting (that with no warning lights) is AC-on.  Unfortunately many people couldn't get their head around this so it was changed in later revisions to AC-on = indicator lit.

 

The compressor fitted to the Superb 2 (and indeed all VW A-platform cars since 2005) is a variable displacement compressor.  Instead of having an electromagnetic clutch that connects or disconnects the drive to the compressor, it instead has a wobble valve that is controlled electromagnetically.  The displacement (and therefore performance and engine load) can be adjusted between 2% and 100% of full capacity.  The climate control module selects the required compressor output depending on things like cooling demand, outside/inside temperature difference, system high-side and low-side pressure, the risk of evaporator freezing,  etc.  

 

The control module also turns the compressor back to minimum setting when engine load demand is high (e.g. during overtaking where the accelerator is fully depressed) to ensure that the maximum torque is delivered to the wheels.

 

When you press the AC button to turn it off, the system selects the minimum setting (i.e. 2%).  It's never turned completely off and is always spinning while the engine is running.

[kwmax]

Wokwon thanks question answered