Hello all, i am looking for a bit of guidance on what to check.. i have a open vent central heating system (halstead best 40 boiler) on 8mm central heating pipes and have just noticed that not all radiators are hot.. all ground floor rads are hot and fine but the upstairs is not, only the bathroom is hot, the other 3 rads are flat cold.. i tried to bleed them with no effect as they did not need doing, but then realised that the actual feed to the radiators from under the floor is stone cold..
I was wondering could it be an airlock, i have no problems with pressure at any of the taps though..if so how do you clear it.
Also when the central heating system fires up the pipes sound like there is not much water in them,they gurgle, i have also noticed the boiler has started to make a quiet bang (1 out of 3 times approx)when switched off on the room stat, i dont think this is doing the system any good and would like advice on how to sort it out..
Many thanx Alan
