can a hot water heater replace boiler?

can i replace my boiler with a hot water heater,and have a heater for my heat and a heater for my on personal water, i have an appollo boiler,it has busted.model#pr650novt,serial#bo1209980, 11 yrs. old,leaking from inside needs replacing, it heats house and also is used for my personal water, so i would like to know if i can have two seperate hot water heaters, one for my water usage and one for my heat.mfgr state select.