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Rheem 621623 - PROG48-40U RH58 Professional Classic Ultra Low NOx Water Heater, Natural Gas, 40K BTU, 48 Gallon, Tall

Item: PROG4840U-621623
MFR: 621623

This product is no longer available for purchase.

Comparable Products


Professional Classic™ Ultra Low NOx gas water heaters are SCAQMD rule 1121 compliant with 10 ng/J NOx emissions

  • .58 - .62 EF
  • More hot water at a low operating cost

  • FHR: 53 - 91 gallons for natural gas
  • Recovery rate is 30.3 - 40.4 gallons for natural gas at a 90 degree rise

Guardian System™ and Sensor
  • Exclusive air/fuel shut-off device for double protection
  • Maintenance free - no filter to clean

Low Emissions
  • Ultra Low NOx radiant burner design
  • Stainless steel construction
  • SCAQMD Rule 1121 compliant
  • Meets 10 ng/J NOx requirements

  • EverKleen™ patented system fights sediment build-up
  • Reduces fuel costs
  • Provides more hot water

Easy to Light
  • No matches required

Longer Life
  • Rheem exclusive R-Tech (resistored) anode rod provides long-lasting tank protection

High Altitude Compliant
  • Certified to 10,200 ft. above sea level

  • Enhanced flow brass drain valve
  • Temperature and pressure relief valve included
  • Low lead compliant
  • Exclusive Rheemglas® lining

  • 6-Year limited tank and parts warranty*
  • With ProtectionPlus™ the 6-year limited tank warranty becomes 10-year
  • * See Residential Warranty Certificate for complete information

Units meet or exceed ANSI requirements and have been tested according to D.O.E. procedures. Units meet or exceed the energy efficiency requirements of NAECA, ASHRAE standard 90, ICC Code and all state energy efficiency performance criteria.


NameRheem 621623 - PROG48-40U RH58 Professional Classic Ultra Low NOx Water Heater, Natural Gas, 40K BTU, 48 Gallon, Tall
Gemaire Item NumberPROG4840U-621623
Manufacturer Product Number621623
SKU - PIM Number1404399735290
ERP Number344590
Unit of MeasureEA
Weight135.0 Pounds (Lb)
Length20.1 Inches (In)
Width20.1 Inches (In)
Height60.7 Inches (In)
Country of OriginMEX
BTU Input40000
Capacity Gallons48
Connection Size3/4"
Fuel TypeNatural Gas
Warranty OfferedYes
Energy Star RatedNo
UL ListedNo
Product FamilyPROG
GEM - Case Quantity


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