The only thing in a typical home that needs fairly hot water is the dishwasher. But, at least some of them can heat their own water if the incoming water isn't hot enough. Without one or the other, the DW will not perform very well. same is true with a washing machine...many stains and things can be removed with cold water. But, should you need hot, some of them can heat the water, or will require greater than the nominal 110-degree water that may be fine for bathing. So, it really depends on what your needs and desires are.