I have fixed a couple of broken wires below the fan controller and the aircon now blows cold when you start the car but after a few minutes it goes warm. A few more minutes it goes cold and continues to alternate like this. Any pointers or places to focus my attention.

Hi, welcome to Briskoda.

 

I would start with a check on the gas level, did it blow cold consistently before the wiring repairs?.

 

If all is correct on the gas level I would move on to a fault code scan to make sure all is well with the system. You do not say which model or year of Octavia that you have, does it have Climatronic or basic a/c?.

Kentphil, I will get the gas levels checked, I did try to get it checked before but the compressor wasn't kicking in due to the wiring fault. I do know it was showing a static pressure of 5 bar. The aircon was not working at all prior to fixing the wiring. It seems to blow nice and cold when it's cold it really is like it alternates between warm and cold for a couple of minutes each. It's an 04 plate Mk1 Octavia with climatronic. When the air con wasn't working it was showing no faults if I put the aircon into diagnostic mode I will check again tomorrow.

The gas level is done by weight of gas on these models, so a check at a specialist would be my next action.

5 bar at what temperature?

 

Are the fans cutting in now and remaining running?

 

VCDS will show you what the compressor cut off codes are, sounds like its cycling because the high side is going too high, normally that would be fans not operating.

Annoyingly I can only get it to run warm when moving will try again, so can't see if the fans have stopped running or not. Will get the gas level checked fully.

12 hours ago, Bigsurfer said:

04 plate Mk1 Octavia with climatronic.

Does the outside temperature readout (in Climatronic display, and echoed in trip computer) stay constant and believable or vary between cold and hot?

The outside temp stays constant on both the climatronic and dash and seems pretty close to actual temp.

4 hours ago, Bigsurfer said:

The outside temp stays constant on both the climatronic and dash and seems pretty close to actual temp.

Cheers. Not what I'd wondered about then.