www.phcppros.com/articles/6860-rinnai-m-series-condensing-gas-boiler

Rinnai M-Series Condensing Gas Boiler
January 31, 2018
With an increased heating output range, increased hot water output and increased heat exchange performance, the new M-Series Condensing Gas Boiler delivers high performance. The heat engine combines new burner technology with a stainless-steel water heat exchanger for improved efficiency, lower emissions, increased reliability and fast response.
A smaller footprint and lighter design help with installation.
All service points have been moved to the front left side of the unit; users just need to lift and remove the cover for full access.
Rinnai