Air conditioning problems

[mijango]

Our air conditioning has started acting a little strange.
1. When we first start up the vehicle it used to cool down the vehicle very quickly, however it now takes a lot longer to do this (I.e the air seems warmer than before). It’s almost as though the vehicle needs to be moving quickly to get enough air flow through to be cooled.
2. Once the vehicle has cooled down it seems to keep on blowing cool air (as thought the thermostat has stopped working). This makes it colder than the temperature set.
Anyone have any advice/ experience of this?

[Aussie Jeepster]

Mine was a little anemic when I first collected it, but a trip to the local aircon specialist diagnosed low on gas.
They found a tiny weep, fixed it, re-gased it and it has been great for the last 12 months.
Air conditioning is a black science to me, so I let others sort it!
Alan

[kelvo]

I recall mention of a variable loading valve in the air con compressor, so it can work like a house inverter air conditioner. This allows the compressor to run at 100% capacity when required, but to then back off as the temp in the car gets cooler. This improves the fuel economy. It sounds like yours may have failed/got stuck in a ‘mid capacity’ position.

[DiscoJeffster]

Yes. I have one of the valves on my shelf and need to replace mine. Can’t remember it’s name but it’s the control valve for the variable displacement compressor. I need to get my system degassed and get a small amount of positive pressure into it with nitrogen to help force it out. It’s costly to replace but relatively easy. The AC place will remove the circlip holding it in then nitrogen pressurise the system to blow it out. It’s pretty tight with the orings bound in place.
About $800 I was quoted to have replaced including valve. Valve is around $100 of it. Mostly labour and Doscovery tax.