Ok. Just had a Vaillant 837 installed and all seems well, except that when I run a cold tap, the boiler pump starts up. Not the burner, just the pump. Can't understand this as surely a cold tap should have no effect on the boiler?
Any ideas whether this is normal. seems pretty inefficient to me. I am nervous that the installer scr*wed something up.
Thanks
G
Any ideas whether this is normal. seems pretty inefficient to me. I am nervous that the installer scr*wed something up.
Thanks
G