now chris you should know by now someone will have areason/reg not to do it that way as it is the best solution in lofts,i am sure someone will/has put the condense into the tanks rather than run 11/4 all the way through the house with the correct falls/materials.how many safety release pipes have you come across capped/not installed/not run to outside or better still the filling loop connected to the safety release.open the prv to fill the heating came across a few of these years ago mainly valliant odd vokera the mind boggles at what some people do