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Lochinvar

Lochinvar EnergyRite ERN-501 100-Gallon Commercial Gas Water Heater

Model ERN-501
4.2/5 from 60 ratings
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Btu
500000
Venting
Atmospheric
Fuel Type
Natural Gas
Tank Type
Commercial
Energy Factor
0.81
Warranty Years
5

Lochinvar EnergyRite ERN-501 100-Gallon Commercial Gas Water Heater Review

The Lochinvar EnergyRite ERN-501 100-Gallon Commercial Gas Water Heater is a larger commercial gas tank in Lochinvar's EnergyRite line. 500K BTU input for very high recovery rates.

Specs: 100 gallons stored, 500,000 BTU input, UEF 0.62, 480-gallon FHR, 3-year commercial tank warranty. Power-vent PVC venting.

The 500K BTU burner produces extreme recovery rates appropriate for substantial commercial applications: restaurants, large salon/spas, multi-family residential, industrial process. Far exceeds typical residential needs.

About $5,500 unit, $9,000-$12,000 installed depending on commercial gas line and venting work. Right buyer: commercial application with continuous high-demand cycles.

Pros
  • Natural gas combustion — faster recovery than electric resistance at comparable tank size
  • Large 100-gallon reserve — comfortably serves 5+ person households in peak-use periods
  • High 500K BTU input — rapid recovery for large-volume commercial-residential applications
Cons
  • 5-year warranty — below the 8–12 year average for premium models in this class
  • Atmospheric venting requires vertical B-vent — less routing flexibility than power-vent or condensing alternatives

Full Specifications

Brand
Lochinvar
Model Number
ERN-501
Btu
500000
Venting
Atmospheric
Fuel Type
Natural Gas
Tank Type
Commercial
Energy Factor
0.81
Warranty Years
5
Capacity Gallons
100

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