Finally managed to resolve all problems we were experiencing!!! and thought I'd post the solution.
Whilst staring at the boiler/pump waiting for inspiration, I noticed an anti-gravity valve in a section of pipe above the pump, I removed the valve and found it was full of debris and as such wasn't operating. I replaced the valve and re-filled the system, there was a slight improvement but still didn't have all the rads working!
I had nothing left to try, so with the CH switched on (i.e. 3 rads hot and the others still cold) and with the mains water still on, I began to drain the system hoping to 'pull/push' the hot water around the CH system..... and within 30-60 mins had all the rads working!
I tested the CH (on max) over the next few days and had no problems.
Thanks again too everyone who helped,
P.S. The delay is because we have just had a baby, but at least she came home to a warm house!
Whilst staring at the boiler/pump waiting for inspiration, I noticed an anti-gravity valve in a section of pipe above the pump, I removed the valve and found it was full of debris and as such wasn't operating. I replaced the valve and re-filled the system, there was a slight improvement but still didn't have all the rads working!
I had nothing left to try, so with the CH switched on (i.e. 3 rads hot and the others still cold) and with the mains water still on, I began to drain the system hoping to 'pull/push' the hot water around the CH system..... and within 30-60 mins had all the rads working!
I tested the CH (on max) over the next few days and had no problems.
Thanks again too everyone who helped,
P.S. The delay is because we have just had a baby, but at least she came home to a warm house!
