Imagine this if you would. Your plants down and every pressure relief valve has to be replaced and all the plumbing attatched to it. So we have contractors come in to do this choir. 1:30 in the afternoon your bleeding out the liquid side of a thermosypon. So the srv's can be changed. Then bam contractor takes off the WRONG srv valve and now you got your second stage pouring out of a 1.25 inch hole. Now you can thank god that you had to bleed that out a week ago and only had some residual gas build up in it......... Couple days later...... (scratches head) We evacuated a thermosypon cooler and it had been open for a couple of days then the return line seat on the valve let go..... Again pouring wet gas out........ Glad to be back up and running now.