Rafal Kaczynski
Dear Renecca I understand that your main question is what heating system Should be fitted to replace an old Vented Hot Water System;) I would suggest if you have a space for Unvented Hot Water Cylinder along with Condensing boiler as UHWS work under main water pressure so hot water is always hot in many off draw off points in your house. For instance if someone is washing plates in a kitchen and you are taking a shower water temp won't change as is taken from cylinder. Advantage as well to fit this system is that CH work as well while water is heated for taps. If you do not have a space for that cylinder go for condensing combi boiler only . I hope this will help you to choose right system for your house. Regards Rafal
