The Bosch Greenstar models listed below offer an altitude compensation feature that allows the boiler to operate at altitudes of up to�6000' without any reduction in capacity. Beyond 6000' the boiler output will fall by 3% per 1000'. Further details on high altitude compensation and derate can be found on page 57 of the installation manual.�
ZBR16-3A, ZBR21-3A, ZBR28-3A, ZBR35-3A, ZWB28-3A, and ZWB35-3A