waterheaterspecs

Gas storage water heaters

The gas storage group holds 134 certified model numbers in 19 rating sets, from 14 brands. HTP PH76-80 has the highest first-hour rating of any tank on the list, 206 gal, from 77 gal of rated volume. HTP PH100-80 has the highest UEF of all 15 high-draw residential-duty commercial gas storage sets on the list, 0.93. American PG10 34 100 2V 2 turns 33 gal of rated volume into 170 gal in the first hour, 5.15 per rated gallon, the highest ratio among the tanks here. Of the group’s model numbers, 96% share every certified rating with a model sold under another brand name, the highest share of the four heater types on this site.

Certified models as of October 27, 2026 · Open this type in the Heater finder

First-hour rating against rated volume, every gas storage set on the list

Gas storage setsOther sets of the same type

First-hour rating, gal

First-hour rating against rated volume, every gas storage set on the list8012016020030405060708090100110120Rated volume, gal2×3×Rheem ECE G40-50U CN HERheem ECE G50-50U CN HEA. O. Smith GC6-PS4050V 1A. O. Smith GC6-PS5065V 1Rheem PROPG75-100P RH HE EC3Rheem ECE G50-100U CN HE EC3Rheem ECE G50-76U CN HE EC3GSW 6G5076NVC 1A. O. Smith GDHE-50 3A. O. Smith GDHE-75 3A. O. Smith HDHE-50 4A. O. Smith HDHE-75 4American PG10 34 100 2V 2HTP PH100-119HTP PH100-55HTP PH100-80HTP PH76-50HTP PH76-60HTP PH76-80
First-hour rating against rated volume, every gas storage set on the list80120160200306090120Rated volume, galRheem ECE G40-50U CN HERheem ECE G50-50U CN HEA. O. Smith GC6-PS4050V 1A. O. Smith GC6-PS5065V 1Rheem PROPG75-100P RH HE EC3Rheem ECE G50-100U CN HE EC3Rheem ECE G50-76U CN HE EC3GSW 6G5076NVC 1A. O. Smith GDHE-50 3A. O. Smith GDHE-75 3A. O. Smith HDHE-50 4A. O. Smith HDHE-75 4American PG10 34 100 2V 2HTP PH100-119HTP PH100-55HTP PH100-80HTP PH76-50HTP PH76-60HTP PH76-80
Each circle is one rating set; filled circles grow with the number of model numbers. Dashed lines mark first-hour output of 2× and 3× the rated volume.

Every rating set

Sorted by first-hour rating.

Gas storage rating sets
Rating setRated volumeFirst-hour ratingUEFGas useGas inputFuel
Gas storage4 of 4 sets, all high draw
A. O. Smith GC6-PS5065V 1Also listed as American, Envirosense, Envirosense Enercare, Envirosense Reliance Home Comfort, Lochinvar, Reliance, State
Show 16 model numbers
  • A. O. Smith GC6-PS5065*V 1**, GC9-PS5065NV 1**, GPCC-50X 1**, GPCX-50L 1**, HPCX-50L 1**
  • American PCG62-50S65L 1**, PCG82-50S65L 1**
  • Envirosense ENV-50N 1**, ENV-50P 1**
  • Envirosense Enercare ENV-50N-ENER 1**
  • Envirosense Reliance Home Comfort ENV-50N-RHC 1**
  • Lochinvar LHPCX-50L 1**
  • Reliance 6-50-*XPCS 1**, 9-50-YXPCS 1**
  • State GP6-50-*XPCSL 1**, GP8-50-YXPCSL 1**
49 gal118 gal0.90188 therms/yr65,000 Btu/hnatural gas or propane
Rheem ECE G50-50U CN HEAlso listed as Friedrich, Richmond, Ruud
Show 19 model numbers
  • Friedrich 12PROG 50-50P FD HE EC3, 12PROG 50-50U FD HE EC3, 8PROG 50-50P FD HE EC1, 8PROG 50-50U FD HE EC1
  • Rheem ECE G50-50U CN HE*, PRO+G50-50P RH HE EC1, PRO+G50-50U RH HE EC1, PROP G50-50* CN HE**, PROP G50-50* RH HE EC3, XG50T09UHN50U0, XG50T12UHN50*, XP50T09UHN50U0, XP50T12UHC50*
  • Richmond 12GUH50-50F*, 9GUH50-50FN, 9GUH50-50FP
  • Ruud PRO+G50-50P RU HE EC1, PRO+G50-50U RU HE EC1, PROU G50-50* RU HE EC3
50 gal95 gal0.88192 therms/yr50,000 Btu/hnatural gas or propane
Rheem ECE G40-50U CN HEAlso listed as Friedrich, Richmond, Ruud
Show 19 model numbers
  • Friedrich 12PROG 40-50P FD HE EC3, 12PROG 40-50U FD HE EC3, 8PROG 40-50P FD HE EC1, 8PROG 40-50U FD HE EC1
  • Rheem ECE G40-50U CN HE*, PRO+G40-50P RH HE EC1, PRO+G40-50U RH HE EC1, PROP G40-50* CN HE**, PROP G40-50* RH HE EC3, XG40S12UHN50*, XG40T09UHN50U0, XP40S12UHC50*, XP40T09UHC50U0
  • Richmond 12GUH40-50F*, 9GUH40-50FN, 9GUH40-50FP
  • Ruud PRO+G40-50P RU HE EC1, PRO+G40-50U RU HE EC1, PROU G40-50* RU HE EC3
40 gal88 gal0.90188 therms/yr50,000 Btu/hnatural gas or propane
A. O. Smith GC6-PS4050V 1Also listed as American, Envirosense, Envirosense Enercare, Envirosense Reliance Home Comfort, Lochinvar, Reliance, State
Show 16 model numbers
  • A. O. Smith GC6-PS4050*V 1**, GC9-PS4050NV 1**, GPCC-40L 1**, GPCT-40L 1**, HPCT-40L 1**
  • American PCG62-40S50L 1**, PCG82-40S50L 1**
  • Envirosense ENV-40N 1**, ENV-40P 1**
  • Envirosense Enercare ENV-40N-ENER 1**
  • Envirosense Reliance Home Comfort ENV-40N-RHC 1**
  • Lochinvar LHPCT-40L 1**
  • Reliance 6-40-*RPCS 1**, 9-40-YRPCS 1**
  • State GP6-40-*RPCSL 1**, GP8-40-YRPCSL 1**
38 gal86 gal0.90188 therms/yr50,000 Btu/hnatural gas or propane
Gas storage, residential-duty commercial15 of 15 sets, all high draw
HTP PH76-80
Show 1 model number
  • HTP PH76-80****
77 gal206 gal0.87195 therms/yr76,000 Btu/hnatural gas or propane
Rheem PROPG75-100P RH HE EC3Also listed as Friedrich, Richmond, Ruud
Show 10 model numbers
  • Friedrich 12PROG 75-100P FD HE EC3, 12PROG 75-100U FD HE EC3
  • Rheem PROPG75-100P RH HE EC3, PROPG75-100U RH HE EC3, XG75T12UHN100U0, XP75T12UHC100U0
  • Richmond 12GUH75-100FN, 12GUH75-100FP
  • Ruud PROUG75-100P RU HE EC3, PROUG75-100U RU HE EC3
75 gal199 gal0.88192 therms/yr100,000 Btu/hnatural gas or propane
HTP PH100-55
Show 1 model number
  • HTP PH100-55****
53 gal187 gal0.89190 therms/yr100,000 Btu/hnatural gas or propane
HTP PH100-119
Show 1 model number
  • HTP PH100-119****
112 gal178 gal0.90188 therms/yr100,000 Btu/hnatural gas or propane
American PG10 34 100 2V 2Also listed as A. O. Smith, State
Show 4 model numbers
  • A. O. Smith GSP-100 2**
  • American PG10 34 100 2*V 2**, PR-34-100 * 2**
  • State GHX-34-100 N 2**
33 gal170 gal0.90188 therms/yr100,000 Btu/hnatural gas or propane
Rheem ECE G50-100U CN HE EC3Also listed as Friedrich, Richmond, Ruud
Show 9 model numbers
  • Friedrich 12PROG 50-100P FD HE EC3, 12PROG 50-100U FD HE EC3
  • Rheem ECE G50-100U CN HE EC3, PROP G50-100* CN HE EC3, PROP G50-100* RH HE EC3, XG50T12UHN100*0, XP50T12UHC100U0
  • Richmond 12GUH50-100F*
  • Ruud PROU G50-100* RU HE EC3
50 gal167 gal0.89190 therms/yr100,000 Btu/hnatural gas or propane
HTP PH76-60
Show 1 model number
  • HTP PH76-60****
58 gal157 gal0.88192 therms/yr76,000 Btu/hnatural gas or propane
HTP PH76-50
Show 1 model number
  • HTP PH76-50****
48 gal154 gal0.90188 therms/yr76,000 Btu/hnatural gas or propane
A. O. Smith HDHE-75 4Also listed as American, GSW, Reliance, State
Show 5 model numbers
  • A. O. Smith HDHE-75 4**
  • American VG8275T100*V
  • GSW 8G-75100*PDV-H06* 4**
  • Reliance 8-75-*TPDT 4**
  • State GP-8-75-*TPDT 4**
74 gal150 gal0.86197 therms/yr100,000 Btu/hnatural gas or propane
Rheem ECE G50-76U CN HE EC3Also listed as Friedrich, Richmond, Ruud
Show 9 model numbers
  • Friedrich 12PROG 50-76P FD HE EC3, 12PROG 50-76U FD HE EC3
  • Rheem ECE G50-76U CN HE EC3, PROP G50-76* CN HE EC3, PROP G50-76* RH HE EC3, XG50T12UHN76*0, XP50T12UHC76U0
  • Richmond 12GUH50-76F*
  • Ruud PROU G50-76* RU HE EC3
50 gal136 gal0.89190 therms/yr76,000 Btu/hnatural gas or propane
HTP PH100-80
Show 1 model number
  • HTP PH100-80****
75 gal132 gal0.93182 therms/yr100,000 Btu/hnatural gas or propane
A. O. Smith GDHE-75 3Also listed as American, GSW, Reliance, State
Show 5 model numbers
  • A. O. Smith GDHE-75 3**
  • American VG6275T100*V 3**
  • GSW 6G75100*PDVH0* 3**
  • Reliance 6-75- *TPDT 3**
  • State GP6-75- *TPDT 3**
74 gal130 gal0.86197 therms/yr100,000 Btu/hnatural gas or propane
GSW 6G5076NVC 1Also listed as A. O. Smith, American, Reliance, State
Show 6 model numbers
  • A. O. Smith GPHE-50 1**
  • American VG6250T76NV 1**
  • GSW 6G5076NVC 1**, 6G5076NVC02 1**
  • Reliance 6-50-YTVIT 1**
  • State GP6-50-YTVIT 1**
48 gal119 gal0.88192 therms/yr76,000 Btu/hnatural gas only
A. O. Smith HDHE-50 4Also listed as American, GSW, Reliance, State
Show 5 model numbers
  • A. O. Smith HDHE-50 4**
  • American VG8250T100*V
  • GSW 8G-50100*PDV-H06* 4**
  • Reliance 8-50-*TPDT 4**
  • State GP-8-50-*TPDT 4**
49 gal118 gal0.88192 therms/yr100,000 Btu/hnatural gas or propane
A. O. Smith GDHE-50 3Also listed as American, GSW, Reliance, State
Show 5 model numbers
  • A. O. Smith GDHE-50 3**
  • American VG6250T100*V 3**
  • GSW 6G50100*PDVH 3**
  • Reliance 6-50-*TPDT 3**
  • State GP6-50-*TPDT 3**
49 gal100 gal0.88192 therms/yr100,000 Btu/hnatural gas or propane

One rating, eight brand names

16

model numbers here share every certified value of A. O. Smith GC6-PS5065V 1: 49 gal rated, 118 gal first hour, UEF 0.90.

Why one rating set carries several brand names

Model numbers in that set, by brand

  • A. O. Smith5
  • American2
  • Envirosense2
  • Reliance2
  • State2
  • Envirosense Enercare1
  • Envirosense Reliance Home Comfort1
  • Lochinvar1

Fuel listing

Counted by model number. Separate natural-gas and propane versions of one heater usually carry their own model numbers.

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