STATE GPCT-40L 1**

This site calculated the 188 therms figure; it was not taken from the registry. The calculation uses the registry's UEF, the ratio of hot water delivered to energy used, and the daily draw that the DOE test sets for the high draw pattern. This model's UEF is 0.9. The source is the DOE Compliance Certification Database, retrieved 2026-09-19. Among the 414 gas tank models registered at the high draw pattern, this model ranks 1st lowest in energy use. The figure applies only at the test's daily draw. A household that uses more or less hot water will use a different amount of gas. The page on how this site calculates annual energy and cost sets out each step.

The high draw pattern describes a larger household, or one where showers and laundry overlap. This tank has a rated volume of 38 gallons. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 86 gallons. A home that needs more than 86 gallons in its busiest hour would need more than this rating covers. A smaller household with lighter use falls outside the high draw pattern. This page has no energy figure for that lower use, so it is not available here. To compare other units, the water heater selector by fuel, space and size lists models by those three filters.

The running cost is not written here because it depends on your state's average residential gas price. The page works it out from your ZIP by applying that price to the 188 therms of natural gas at the high draw pattern. The cost calculator for your own ZIP shows the same calculation on a separate page. This model has no published installed price range. Its ratings lie outside the range that the cost database's model was fitted on, and the site does not stretch that range to cover it. A plumber or seller checking a swap can use the same-class replacement search by model number to find other gas tank models registered at the high draw pattern.