How does Rinnai calculate their claim of typical hot water heating savings of up to 10%?

Savings are influenced by a number of factors including cylinder size, hot water use profiles and plumbing system design. Savings of up to 10% have been observed.

The savings claim is verified by results from European tapping tests. The European efficiency testing standard for a hot water system uses “tapping’s”. Tapping's are calls for hot water from the cylinder at various times to simulate real life hot water use.