There should still be some updates demanded. Such as, new condensing boilers will need a ‘condense pipe’ operate within the boiler to the drain (inside or exterior). Combi boilers over 18kW would require a 22mm gasoline pipe. If your current gasoline pipe is 15mm it will eventually must be re-run. http://juliusjhbun.getblogs.net/27641571/5-simple-techniques-for-boiler-installation-kent