Boilers account for about 55 per cent of what you spend in a year on energy bills, so an efficient boiler makes a big difference. Call to confirm plumbing service for your home. Up to 30% saving is based on sedbuk figures when replacing g rated with a rated boiler. I've tried other natural drain cleaners and nothing had worked until i found drainbo since i started using, i no longer have a slow shower drain.. no more puddles yay!!!.