I have a question regarding system pressure with my Eko 40 boiler setup. I have read and been told that the system should be set around 12 pounds of pressure. Does this mean 12 pounds when the boiler is cold or hot? Currently, I have 12 pounds of pressure when the boiler is hot, and when it is cold, the pressure drops to 0. If I boost the pressure to 12 pounds when it is cold, it jumps to between 25-30 pounds of pressure when it is hot.