We have recently moved into a house and when turning on the central heating there is a lot of noise coming from some of the radiators (sounds like water gushing). I have bled most of the radiators and this has solved the problem but there are a few which do not have a valve to turn. In addition there is one which as soon as I turned the key water came gushing out of a hole by the side of the valve. What can I do about the radiatiors without valves and should I drain the water from the other radiatior?
Thanks