Having spent a lot of time worrying, asking questions, having a new cylinder and now changing the pipework and having new pumps fitted I think that I have just realised what my original problem was.
I had gravity HW and pumped CH. Every now and again when the CH clicked off there would be an almighty racket and water would pour out of the overflow.
I think this was caused by a low pump speed causing the boiler to overheat and then when the pump switched off all of this heat shot up the vent. Might I be right? The boiler had been kettling for some time.
The reason I had a low pump speed was because when set higher it woke me up - even though the pump was in the kitchen. I now have a grundfos pump plan in the airing cupboard and I cant sleep at all with the racket it is making but if I turn the CH pump down to 1 then no doubt I will be back to sqaure 1.
After the new cylinder was fitted the engineer did turn the pump speed up but I turned it down again so I didnt give it time to see if the overflow problem was likely to happen on a higher speed - and in any case I didnt know this might be connected.
Have I just spent a small fortune for nothing? And I'm still not going to get any sleep!
I had gravity HW and pumped CH. Every now and again when the CH clicked off there would be an almighty racket and water would pour out of the overflow.
I think this was caused by a low pump speed causing the boiler to overheat and then when the pump switched off all of this heat shot up the vent. Might I be right? The boiler had been kettling for some time.
The reason I had a low pump speed was because when set higher it woke me up - even though the pump was in the kitchen. I now have a grundfos pump plan in the airing cupboard and I cant sleep at all with the racket it is making but if I turn the CH pump down to 1 then no doubt I will be back to sqaure 1.
After the new cylinder was fitted the engineer did turn the pump speed up but I turned it down again so I didnt give it time to see if the overflow problem was likely to happen on a higher speed - and in any case I didnt know this might be connected.
Have I just spent a small fortune for nothing? And I'm still not going to get any sleep!