I'm looking to replace a broken AC rad/condenser on my Focus. Long story short I crashed the car and the condenser is quite bent. When I got out of the car I could hear a gas escaping from somewhere, and a helpful guy who stopped to check I was OK said it was the AC system.

What I want to know is whether the system has been vented, meaning I can remove it, and if an air con recharge place can completely refill the system.

I've sheepishly opened a valve to the top nearside with a rag over, and nothing came out. Does this mean it is empty? Here's a picture of the valve -


Thanks