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ASHRAE90.1-2010 specifies two resuirements for Gas stoarge water heaters in TABLE 7.8. One is Et = 80%. The other is SL = Q/800 +110sqrt(V) [Btu/h]. Your calculation of SL is correct, but you should not disregard Et. Apart from SL, Et needs to be input somewhere in the simulation tool you use.

Energy Factor (EF) is an indocator of a water heater's overall energy efficiency. Please refer to the old post: Water Heating Equipment Performance Requirements per ASHRAE 90.1-2007. I'm not familiar with Trace 700, but there should be no building energy simulation tool with an input filed for EF.

You don't need to convert SL to EF, but you may need to convert SL according to the simulation tool you use. For example, SL can be input as Off Cycle/On Cycle Loss Coefficient to Ambient Temperature in EnergyPlus. The unit of this input field is [Btu/h°F] (or [W/K]). SL in ASHRAE 90.1-2010 is based on 70°F (38.9°C) temperature difference between stored water and ambient. In your case, Off Cycle/On Cycle Loss Coefficient to Ambient Temperature should be 2004[Btu/h] / 70[°F] = 28.63[Btu/h°F].

ASHRAE90.1-2010 specifies two resuirements for Gas stoarge water heaters in TABLE 7.8. One is Et = 80%. The other is SL = Q/800 +110sqrt(V) [Btu/h]. Your calculation of SL is correct, but you should not disregard Et. Apart from SL, Et needs to be input somewhere in the simulation tool you use.

Energy Factor (EF) is an indocator of a water heater's overall energy efficiency. Please refer to the old post: Water Heating Equipment Performance Requirements per ASHRAE 90.1-2007. I'm not familiar with Trace 700, but there should be no building energy simulation tool with an input filed for EF.

You don't need to convert SL to EF, but you may need to convert SL according to the simulation tool you use. For example, SL can be input as Off Cycle/On Cycle Loss Coefficient to Ambient Temperature in EnergyPlus. The unit of this input field is [Btu/h°F] (or [W/K]). SL in ASHRAE 90.1-2010 is based on 70°F (38.9°C) temperature difference between stored water and ambient. In If SL of your case, Baseline case is 2004[Btu/h], Off Cycle/On Cycle Loss Coefficient to Ambient Temperature should be 2004[Btu/h] / 70[°F] = 28.63[Btu/h°F].

ASHRAE90.1-2010 specifies two resuirements requirements for Gas stoarge water heaters in TABLE 7.8. One is Et = 80%. The other is SL = Q/800 +110sqrt(V) [Btu/h]. Your calculation of SL is correct, but you should not disregard Et. Apart from SL, Et needs to be input somewhere in the simulation tool you use.

Energy Factor (EF) is an indocator of a water heater's overall energy efficiency. Please refer to the old post: Water Heating Equipment Performance Requirements per ASHRAE 90.1-2007. I'm not familiar with Trace 700, but there should be no building energy simulation tool with an input filed for EF.

You don't need to convert SL to EF, but you may need to convert SL according to the simulation tool you use. For example, SL can be input as Off Cycle/On Cycle Loss Coefficient to Ambient Temperature in EnergyPlus. The unit of this input field is [Btu/h°F] (or [W/K]). SL in ASHRAE 90.1-2010 is based on 70°F (38.9°C) temperature difference between stored water and ambient. If SL of your Baseline case is 2004[Btu/h], Off Cycle/On Cycle Loss Coefficient to Ambient Temperature should be 2004[Btu/h] / 70[°F] = 28.63[Btu/h°F].

You seem to be trying to use the same heating capacity and tank volume as the Proposed case for the Baseline case, but please note that they are not necessarily the same. They are more often different. The service water heating system in the Baseline case shall be sized according to ASHRAE90.1-2010 Section 7.4.1. There is no single sizing calculation. Even ASHRAE Handbook—HVAC Applications provides various sizing options.