Apr0327

Thanks Adamsee, so what you are doing is making the mixer value redundant, its constantly open. Unfortunately I need to keep boiler temp higher for upstairs radiators, and therefore need mixer to do its job (wish my plumber did!) for reduced temperature in underfloor.

Rob99, did you manage to solve this? I have same problem and its driving me mad!! Plumber can't solve it and has gone awol!.