Thanks again John,
I've restricted the flow on the bypass valve and turned the Alpha down to constant setting (II). I'll see if that's enough flow to get at least a little bit of heat into the system. I was also wondering if an auto bypass valve might help.
As you know a bit about pumps do you think this one would be suitable as the documentation says that the original was a grundfos 15-50.
I just can't find out if it's controllable.
I'll speak to my heating engineer and see if he can make the relevant changes (although he's the one who put the alpha on!).
Thanks once again for your help with this enigma! One day I will get it to function correctly
I've restricted the flow on the bypass valve and turned the Alpha down to constant setting (II). I'll see if that's enough flow to get at least a little bit of heat into the system. I was also wondering if an auto bypass valve might help.
As you know a bit about pumps do you think this one would be suitable as the documentation says that the original was a grundfos 15-50.
https://www.NoLinkingToThis/p/grund...5zoyb7cPKrGg5KEHDWkaAqQ8EALw_wcB&gclsrc=aw.ds
I just can't find out if it's controllable.
I'll speak to my heating engineer and see if he can make the relevant changes (although he's the one who put the alpha on!).
Thanks once again for your help with this enigma! One day I will get it to function correctly