Rheem Marathon Lifetime 75-Gallon Electric Water Heater

The Rheem Marathon Lifetime 75-Gallon Electric is the largest-capacity unit in Rheem's premium polybuthylene-tank Marathon line. Lifetime tank warranty because the polybuthylene tank cannot rust through — Marathons installed in the early 1990s are still in service. Right answer for large households committed to long-term residence.

Specs: 75 gallons stored, two 4500W heating elements (240V), UEF 0.93, 89-gallon first-hour rating. Polybuthylene fiberglass-reinforced plastic tank (no anode rod required — there's no steel to corrode), high-efficiency foam insulation. About 51" tall × 28" diameter — wider than the 50-gallon Marathon but shorter, which can help in basement installations with overhead clearance constraints.

The 75-gallon capacity serves households of 5+ people in primary residences. The Marathon's lifetime warranty makes it the highest 30-year ownership value in the electric tank category — buyers staying in the home long enough to need two replacements of a standard tank should have bought one Marathon instead. About $2,499 unit, $3,000 installed.

Right buyer: large family in a long-stay primary residence (15+ years), particularly in hard-water regions where standard electric tanks fail at year 7-9 and the Marathon's immunity to tank corrosion is most valuable. Wrong buyer: short-term residences (5-7 year horizon), small households (50-gallon serves adequately), or homes where heat-pump installation is feasible (heat-pump operating cost is 75% lower).