The AM Series high efficiency water heaters are powerful hot water systems with compact footprints and built-in redundancy. The AM Variable Radial Circulation heat exchanger is highly resistant to scale build-up which increases your ROI, expands the lifetime expectancy of your system and promotes uptime reliability. Multiple units can be installed with near-zero side clearance for larger installations. Internal valves are included providing additional savings on installation costs. AM Series water heaters are available in six sizes from 199 to 1,000 MBH (199 and 250 available in AM Rapid Recovery Integrated only).