For residential projects starting in the 2016 code, the standard water heater is a gas fired tank-less water heater in both the Prescriptive and Performance compliance approaches so using any unit with a tank, and especially an electric water heater will produce a significant penalty.
For commercial projects, the standard water heater under Performance is also a gas water heater. However, under Prescriptive, you are allowed to use an electric water heater. Our recommendation is to submit the DHW using the NRCC-PLB-01 form which is available under the NR T24 Prescriptive forms list.
Under the Calculation Options, bottom left button, click and you will see the NR T24 Performance calculations in the list above. Select this, then on the right unclick DHW from the scope and then rerun and the penalty will be gone.
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