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State GUF-50 1**

State GUF-50 1** is in the DOE listing as of Oct 26, 2026.

  • Gas storage water heater
  • 1 listed model

Not listed as ENERGY STAR certified on Oct 26, 2026.

Its figures are also listed under A. O. Smith GUF-50 1**.

Storage volume
48gallons
UEF
0.70Uniform energy factor
First-hour rating
83gallonsHot water in the first hour
See it among every gas storage model

Advertised and certified figures

State GUF-50 1**: advertised and certified
State GUF-50 1**: advertised and certified Size: advertised 50 gal, certified 48 gal (advertised nominal size, certified storage volume). Size: advertised 48 gal, certified 48 gal (certified storage volume). UEF: advertised 0.70, certified 0.70. UEF: advertised 0.70, certified 0.70 (advertised up to). Size · advertised nominal size, certified storage volume Advertised 50 gal Certified 48 gal Size · certified storage volume Advertised 48 gal Certified 48 gal UEF Advertised 0.70 Certified 0.70 UEF · advertised up to Advertised 0.70 Certified 0.70
FigureAdvertisedCertifiedAdvertiserRead
Size 50 gal, nominal size 48 gal storage volume State Read Oct 5, 2026
Size 48 gal 48 gal storage volume State Read Oct 5, 2026
UEF 0.70 0.70 State Read Oct 5, 2026
UEF up to 0.70 0.70 State Read Oct 5, 2026
First-hour rating 83 gal 83 gal State Read Oct 5, 2026

Certified figures by listed model

Model numberStorage volume (gal)UEFFirst-hour rating (gal)Recovery efficiencyDraw pattern
GS6-50-BFUT 1**480.708373%High

UEF is the uniform energy factor. A dash means the model has no such figure.

It holds 48 gallons in the test, 2 gallons less than its 50-gallon sold size. Over one hour from a full tank, it gave 83 gallons in the test (its first-hour rating). Its tank holds 48 gallons, so reheating adds 35 gallons during the first hour. Of 763 gas storage models, 242 give more hot water in the first hour. The median gas storage model gives 78 gallons in its first hour.

It was not listed as ENERGY STAR certified on Oct 26, 2026. In tests, 70% of the energy it uses ends up as hot water (UEF 0.70). The daily hot water use in the test, called its draw pattern, was high. Of 434 gas storage models with the same draw pattern, 111 have a higher UEF. For its type and draw pattern, the median UEF is 0.66. When it reheats water in the test, 73% of the energy it uses ends up in the water.

Its test figures match those of 3 other basic models. The A. O. Smith, American, and RELIANCE WATER HEATERS brands list one or more of them. For the full group, see the A. O. Smith GUF-50 1**.

It may qualify for 2 rebate programs in 2 states.

Also listed as

They carry every figure in the table above.

Rebates

ProgramStateStatusProgram page
Xcel Energy MINNESOTA RESIDENTIAL ENERGY EFFICIENCY PROGRAMS (gas storage, gas tankless) MN May qualify Its own page
Avista Home and small commercial: HVAC and water heating incentives (gas storage) WA May qualify Its own page

Programs change their terms. Check the program's own page before you buy.

Updated Oct 26, 2026 · Methodology

Not covered

  • Changes to an advertised figure after the date beside it.