I have recently purchased a 3/2.5 house w/ gas heat and hot water due to the rising costs in gas I am looking into replacing water heater, current is 14 yrs old. Heater is in garage on one side of house, 2 baths are on other side of house,and as you would expect it takes forever to get hot water to that side of the house. I am interested in installing an efficient water heater and recirculating pump. I don't even know where to start. I plan to purchase a new water heater, and install pump. Where should the pump go? What size? Current tank is 40 gal, the water lines appear to be in the slab. I have plenty of attic room. Please advise the best course of action.