The good thing about most boilers these days is that they’re sold at around % efficiency give or take a couple of percentage points in fact, if you have a really old, inefficient boiler, a new one could save you up to £! Old, low-efficiency heating systems. The latest the plumbing daily! Apply online via the planning portal. If you or someone you know is deserving of this discount, just let us know and we will be happy to consider it!.