Air con problems - help!

[Tavias]

Long time lurker but not a regular poster so hope this is in the right place - mods feel free to move if not!

 

We've now got a 2014 Octavia estate (2.0tdi) and are having a load of problems with the air con. Stealership are being pretty useless and can't find the fault.

 

Basically, it won't maintain a consistent cabin temperature and does not consistently "condition" (i.e. dry and cool) the air.

 

When the air con is set, either manual or auto, the air con part seems to intermittently drop in and out. One minute you're driving along, air con blowing cool, dry air out and the next the system will start to blow warm, moist, ambient air into the cabin, as though someone just turned off the A/C butten. This happens regardless of what temp the system is set at or what speed the fan is running. Nothing changes with fan speed etc, and you can't hear any noticeable change in noise / speed of airflow but suddenly the cabin temp jumps and all the windows steam up. In an hour long journey it will probably do this 3 or 4 times, each time the air con kicks back in about 5-10 mins later.

 

I'm guessing it's a sensor / control system issue as when it's actually working, the system seems to be able to blow plenty of cold air.

 

Any thoughts / help / suggestions gratefully accepted!

[bob corb]

The system has a couple of fail safe systems which disconnect the compressor if the pressure and temperature go out of range. The pressure switch could be faulty or the system could be over/underfilled. Can you get the refrigerant level checked? It'll need to be drained and measured professionally and then refilled - this is all done as part of an AC service anyway so any garage or mobile AC outfit can check it. If the system has the wrong amount of refrigerant in then this could trip the pressure switch. The correct mass of refrigerant is shown on a sticker on the slam panel. 550g rings a bell?

 

My old Lotus AC wouldn't work if you left the car in the sun. You had to drive away let the air flow over the AC condenser cool the system, drop the pressure and then you can hear the compressor click into action.

 

If your AC system demands the fan to be started (the main front fans can be demanded by the powertrain for engine cooling or exhaust cooling durng regen as well as by the AC system) and it doesn't detect that the refrigerant is being cooled and temp is still rising then it will cut the compressor to prevent it blowing open the emergency refrigerant dump valve with a whoosh and puff of vapour from under the bonnet.

[decuk]

I assume it's under warranty. If they can't sort it. Ask if they would be prepared to let a specialist Auto aircon firm at least check it out. After all the dealer will most likely not employ a specialist in this field, the vehicle technicians there will only have limited experience of standard faults, re- gassing etc. No offence meant against them. I'm a general mechanical maintenance technician, ie I don't specialise in any particular area, but can slove MOST problems, as can they.But.....

[kfckfc]

The car status screen access via the 'Car' button (3rd one down on the right) on the radio can display low level error messages, that screen may indicate an error when the problem occurs?

[andyvee]

Get it scanned with VCDS, until you do all you will get is speculation ...

[Gabbo]

I would keep the pressure on your dealer to fix it.

Ask them to put in writing what they have tried to do to fix the problem.

If  they cannot, ask them to discuss with Skoda UK or escalate the problem yourself.

 

There could be many reasons for this behaviour as Bob say:

  - AC system over/under pressure or faulty sensor or switch

  - Cooling Fan errors

  - Internal climate control sensor problems or stuck control flaps etc

  - Software incompatability

  - etc

 

I would be cautious about taking it to a non-approved garage yourself as the Skoda garage could say this invalidates the warranty or the problems are now caused by changes they have made..

Even if Skoda agree for you to take it to a specialist, Skoda should do this for you so you don't incurr any costs or inconvenience.

[Gabbo]

Another thought, when the AC cut-out occurs have you been driving very hard or overtaking ??

The AC system will temporarily cut-out when the driver accelerates hard to allow for full-power for overtaking or towing up a hill.

 

This should only be temporary though & the AC system should restart automatically after a short time.

[Gabbo]

One thing you could try to isolate the source of the problem:

 

Run the car at idle with AC on & the climate control set to LO.

This should mean that the system provides maximum cooling & the climate control system inside the car shouldn't try to maintain a "temperature" just flow 100% cooled air.

 

Check the radiator fan at the front of the car is running.

If the AC still cuts-out in this condition, it would suggest its more a problem with the refridgerant system (filling levels or pressure switches/sensors)

[andyvee]

What drive mode are you in and what mode is the climate in (low, medium etc)

Sent from my HTC One_M8 using Tapatalk