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Marathon Heavy Duty Lifetime 50-Gallon Electric Water Heater

Model MHD50245
4.7/5 from 340 ratings
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Kw
5.5
Voltage
240V
Amperage
30A
Fuel Type
Electric
Tank Type
Tank
Energy Factor
0.92

Marathon Heavy Duty Lifetime 50-Gallon Electric Water Heater Review

The Marathon Heavy Duty Lifetime 50-Gallon Electric is a premium variant of the standard Marathon 50-gallon, with enhanced features for higher-cycle applications. The "Heavy Duty" designation reflects commercial-leaning specs while retaining the consumer lifetime warranty.

Specs: 50 gallons stored, two 6000W heating elements (versus standard 4500W in regular Marathon), UEF 0.95, 70-gallon first-hour rating, lifetime tank warranty + 6-year parts warranty. Polybuthylene fiberglass-reinforced plastic tank (no anode rod required).

Heavy Duty differentiators versus standard Marathon 50-gallon:

  • 6000W elements (vs 4500W) deliver faster recovery: 28 gph at 90°F rise vs 21 gph
  • Higher first-hour rating: 70 gallons vs 62 gallons
  • Heavier-duty wiring and circuit requirements (40A 240V vs 30A 240V)
  • Same lifetime polybuthylene tank construction

The Heavy Duty positioning targets households where 50-gallon electric resistance recovery typically becomes a constraint — 4-person households with overlapping demand. The faster element output partially compensates for electric's slower recovery versus gas.

About $2,300 unit, $2,900 installed. Right buyer: long-stay primary residence with 4-person household and electric utility only, where the Marathon's lifetime warranty matters and the standard 50-gallon's recovery rate would be tight.

Pros
  • No combustion, no venting required — installs anywhere with 240V electrical access
  • Strong UEF 0.92 efficiency — approximately 20% lower annual operating cost vs 0.62 standard
  • 99-year warranty — top-tier coverage for residential water heaters
  • 50-gallon capacity — right-sized for 3–4 person households with standard usage patterns
Cons
  • Resistance electric has slower recovery than gas at comparable capacity — schedule heavy use to match tank recovery

Full Specifications

Brand
Marathon
Model Number
MHD50245
Kw
5.5
Voltage
240V
Amperage
30A
Fuel Type
Electric
Tank Type
Tank
Energy Factor
0.92
Warranty Years
99
Capacity Gallons
50
First Hour Delivery
78

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