Hi Murphy's law - my CO2 ran out on 30th December and the nearest refill centre was closed until January 3rd. As I was also away for the New Year festivities I put the cylinder in the boot of my car, where it stayed in below freezing temperatures until yesterday when I managed to get a refill. The chap at the refill centre was surprised how easily the 2kg bottle filled, apparantly they normally have to 'fill' them twice, once to get the temperature down enough to then get the correct weight of liquid gas inserted. He even had to let some out to make the correct weight. Several hours after I reconnected the system which is housed in the cabinet below the tank I was surprised to see the pressure guage showing 160bar. Being a bit concerned I removed the bottle to the garage overnight. I rang the refill centre but tthe chap there didn't seem overly concerned as he was positive he had added the correct weight. He suggested I release some gas by opening the needle valve and the tap on the pressure reducer or removing the reducer and gently opening the main valve for a few seconds. Not wishing to waste too much gas I opened the reducer valves and when it dropped to around 100 bar I reconnected the system. That was around noon today. It's now 7.25pm and the pressure guage has stayed at 120 bar for a couple of hours now at a room temperature of around 20oC. I read somewhere that the safety valve on these bottles blows off at 3000psi so maybe I'm overly nervous. To be safe I have now positioned the bottle outside the tank cabinet as presumably if the saftey valve blew it would take the side of the cabinet out with disasterous consequences for the tank. This is the first time I've had to refill so not sure if this is all quite normal or if I should release some more gas?