The ENERGY FACTOR is the measure of overall efficiency for water heaters. This measurement is based on three factors: 1) the recovery efficiency, or how efficiently the heat from the energy source is transferred to the water; 2) stand-by losses, or the percentage of heat lost per hour from the stored water compared to the content of the water, and 3) cycling losses.
| Brand Name | Trade Names | Model Number | Rated Volume | Energy Factor |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GCV-30-100 | 28 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPSH-40-200 | 40 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPSH-50-200 | 50 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPSX 50 200 | 50 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPSX 50L 200 | 50 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPSX 50Q 200 | 50 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GVR-40-100 | 40 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GVR-50-100 | 50 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GVRA-40-100 | 40 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GVR-30-100 | 30 | 0.63 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | XGV-40-100 | 40 | 0.63 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | XGV-40L-100 | 40 | 0.63 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | XGV-50-100 | 50 | 0.63 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | XGV-50L-100 | 50 | 0.63 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | XGVL-40-100 | 40 | 0.63 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPCR-40-200 | 40 | 0.64 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPCR-50-200 | 50 | 0.64 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPVH 40* 100 | 40 | 0.65 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPVH 50* 100 | 50 | 0.65 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPVT 40* 100 |
40 | 0.65 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPVT 50* 100 | 50 | 0.65 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPVX 50* 100 | 50 | 0.65 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPVR 40* 100 | 40 | 0.67 |
| A.O. SMITH WATER PRODUCTS CO. | A.O. Smith | GPVR 50* 100 | 50 | 0.67 |
| A.O. SMITH WATER PRODUCTS CO. | ProMax | GDV 40 100 | 40 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | ProMax | GDV 40L 100 | 40 | 0.62 |
| A.O. SMITH WATER PRODUCTS CO. | ProMax | GDV 50 100 | 50 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG12240S403N*** | 40 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG12250T403N*** | 50 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG6240S403N*** | 40 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG6250T403N*** | 50 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG9240S403N*** | 40 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG9250T403N*** | 50 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | SG12140T403N*** | 40 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | SG6140T403N*** | 40 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | SG9140T403N*** | 40 | 0.62 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG12240T403N*** | 40 | 0.63 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG6240T403N*** | 40 | 0.63 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | BFG9240T403N*** | 40 | 0.63 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | PDVG6240T42N*** | 40 | 0.66 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | PDVG6250T42N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | PDVG6250T60N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | PVG6240T42N*** | 40 | 0.66 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | PVG6250T42N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | Ace, American, American Hardware, Americ | PVG6250T60N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PDVG12240T42N*** | 40 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PDVG12250T42N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PDVG12250T60N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PDVG9240T42N*** | 40 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PDVG9250T42N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PDVG9250T60N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PVG12240T42N*** | 40 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PVG12250T42N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PVG12250T60N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PVG9240T42N*** | 40 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PVG9250T42N*** | 50 | 0.66 |
| AMERICAN WATER HEATER COMPANY | XCL Energy Saver, Whirlpool, U.S. Supply, T | PVG9250T60N*** | 50 | 0.66 |
| APOLLO COMFORT PRODUCTS | APOLLO | A** 50 SCVIT L5 200 | 50 | 0.62 |
| APOLLO COMFORT PRODUCTS | APOLLO | A** 50 XSVIT L5 200 | 50 | 0.62 |
| APOLLO COMFORT PRODUCTS | Apollo | A10 40 YXRT L | 40 | 0.63 |
| APOLLO COMFORT PRODUCTS | Apollo | A10 50 YXRT L | 50 | 0.63 |
| APOLLO COMFORT PRODUCTS | Apollo | A6 40 YXRT L | 40 | 0.63 |
| APOLLO COMFORT PRODUCTS | Apollo | A6 50 YXRT L | 50 | 0.63 |
| APOLLO COMFORT PRODUCTS | Apollo | A10 40 YQVIT L2* 10 | 40 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A10 40 YRVIT L2* 100 | 40 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A10 50 YQVIT L2* 10 | 50 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A10 50 YQVIT L5* 10 | 50 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A10 50 YRVIT L2* 100 | 50 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A6 40 YQVIT L2* 100 | 40 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A6 40 YRVIT L2* 100 | 40 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A6 50 YQVIT L2* 100 | 50 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A6 50 YQVIT L5* 100 | 50 | 0.65 |
| APOLLO COMFORT PRODUCTS | Apollo | A6 50 YRVIT L2* 100 | 50 | 0.65 |
| APOLLO COMFORT PRODUCTS | HydroHeat | A6 40 YBDS L | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White | M-4-50S***N-12 | 50 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White | MIITW65T***N12 | 65 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White | M-I-TW40L***N-12 | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White | M-I-TW50L***N-12 | 48 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White | PDX250T***N10 | 48 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White | M1TW40S*FBN(A) | 40 | 0.63 |
| BRADFORD WHITE CORPORATION | Bradford White | M1TW50S*FBN(A) | 50 | 0.63 |
| BRADFORD WHITE CORPORATION | Bradford White | M-4-403T***N-12 | 40 | 0.63 |
| BRADFORD WHITE CORPORATION | Bradford White | M-4-40T***N-12 | 40 | 0.63 |
| BRADFORD WHITE CORPORATION | Bradford White | M-4-50S***N-13 | 50 | 0.63 |
| BRADFORD WHITE CORPORATION | Bradford White | M-I-TW50L***N-13 | 48 | 0.63 |
| BRADFORD WHITE CORPORATION | Bradford White | M-4-403T***N-13 | 40 | 0.64 |
| BRADFORD WHITE CORPORATION | Bradford White | M-4-40T***N-13 | 40 | 0.64 |
| BRADFORD WHITE CORPORATION | Bradford White | MIITW50T***N12 | 48 | 0.64 |
| BRADFORD WHITE CORPORATION | Bradford White | M-I-TW40L***N-13 | 40 | 0.64 |
| BRADFORD WHITE CORPORATION | Bradford White | M-II-TW50T***N-10 | 48 | 0.65 |
| BRADFORD WHITE CORPORATION | Bradford White | M2TW50T*FBN(A) | 48 | 0.66 |
| BRADFORD WHITE CORPORATION | Bradford White | M2TW65T*FBN(A) | 65 | 0.66 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M1TW40S*BN1 | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M1TW50S*BN1 | 50 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M1TW60T*FBN(A) | 60 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M2TW65T*BN1 | 65 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M430T***N7 | 30 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M430T***N7-ATO****** | 30 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M430T*FBN(A) | 30 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M430T*FBN(B) | 30 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4403S***N5 | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4403S***N7 | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4403S***N7-ATO**** | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4403S*FBN(A) | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4403S*FBN(B) | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M440T***N5 | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M440T***N7 | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M440T***N7-ATO****** | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M440T*FBN(A) | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M440T*FBN(B) | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4503*FBN(A) | 50 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4503*FBN(B) | 50 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, JetGlas | M-4-50S**FBN2 | 50 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | MIITW65T***N15 | 65 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | MIITW65T***N15-ATO | 65 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | MITW40L***N15 | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | MITW40L***N15-ATO* | 40 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | MITW50L***N15 | 48 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | MITW50L***N15-ATO* | 48 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | PDX250T***N13 | 48 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | PDX250T***N13-ATO* | 48 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | PDX250T*BN(A) | 48 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | PDX250T*FBN(A) | 48 | 0.62 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4503***N5 | 50 | 0.63 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M4503***N7-ATO****** | 50 | 0.63 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M2TW50T*BN1 | 48 | 0.64 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | M430T***N5 | 30 | 0.64 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | MIITW50T***N15 | 48 | 0.64 |
| BRADFORD WHITE CORPORATION | Bradford White, Jetglas | MIITW50T***N15-ATO | 48 | 0.64 |
| LOCHINVAR CORPORATION | Energy Saver, Golden Knight, Knight | DVN041 | 40 | 0.62 |
| LOCHINVAR CORPORATION | Energy Saver, Golden Knight, Knight | DVN051 | 48 | 0.62 |
| LOCHINVAR CORPORATION | Energy Saver, Golden Knight, Knight | DVN065-2 | 65 | 0.62 |
| LOCHINVAR CORPORATION | Energy Saver, Golden Knight, Knight | LTN030G-EF | 30 | 0.62 |
| LOCHINVAR CORPORATION | Energy Saver, Golden Knight, Knight | LTN040G-EF | 40 | |