My house has hard water. My hot water pressure if very low due to, I assume, the scaling in the tankless coil hot water maker in my boiler which is original to the houe (1959). I plan on upgrading to an indirect water heater. Should I choose an indirect water heat that is a tank-in-tank model, or a coil model? Does either type make a real difference in avoiding hard water scaling within the tank and the reduced efficiency it causes?
Any advice appreciated! -Anthony Falcone