Thanks for your consideration. I have already filled the radiators through the garden hose, before reading all these threds. It was fine last night, all radiators were hot and everybody happy. But next morning, there were "0" PSi, and one of the basebord radiators from basement , was licking through the valve when I have closed it. Of course,this is not the major problem. My question is: why the pressure is "0"?? Since I didn't have problems for ten years with the system, all of sudden I had to learn new things. Maybe this is how should be, maybe, I have to increase the termostat temperature to have the pump working and increase the pressure, which, I did, and still the pressure is "0". Thank you all for your advice.