Newbie question on gas recovery

[bigcw]

Hi everyone

First post, and newbie refrigeration engineer here. I qualified just before Christmas so I am just finding my feet hence why this is probably a very simple question.

I have been tasked with decommissioning an old Denco R22 water chiller but am struggling to work out how to connect my gauges, and therefore my recovery machine, to it. It doesn't seem to have any service valves anywhere, just these schrader-type connections on the high and low pressure sides of the compressors. I seem to remember from my course that we used one of these for the vacuum gauge when pumping down the system.

So my question: can I use these valves for refrigerant recovery?

If I can, do I need some kind of adapter to push down the valve or will my standard hoses work? I've got a Javac gauge set and the standard hoses that came with it if that makes any difference.

If not, what should I be looking for instead to connect to?

I've attached a photo. Note that it has been sat outside for a while hence the rust!

Would appreciate any pointers.

Thanks, Chris