Coil:Heating:DX:SingleSpeed output mismatch query

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For writing an EMS code I am trying to calculate the electrical power draw for a DX:heating coil. Based on the equations mentioned in the Engineering reference I wrote a python code to see if the equations result to the energy plus output. Unfortunately, they don't. Here is the snippet of the simulation variables that was used for calculation along with mine and energyplus outputs. Can anybody point out to what am I doing wrong? The output closely matches electrical energy during no-defrost conditions but is off by quite a big marging when there are defrost periods. I have the code here- https://github.com/TM-Abir-Ahsan/unti...

Output Variables

• MAIN DX HEATING COIL_UNIT1:Heating Coil Heating Energy [J] (TimeStep) = 175901.2156
• Environment:Site Outdoor Air Drybulb Temperature [C] (TimeStep) = 2.7
• Environment:Site Outdoor Air Wetbulb Temperature [C] (TimeStep) = 1.33
• Indoor Air Wetbulb Temperature [C] (TimeStep) = 12.11
• Max Outdoor Temperature for Defrost [C] = 5
• Rated heating capacity [W] = 14333.9065
• Rated COP = 3.837798295
• Timestep = 60 (1 min step)

Eplus Outputs

• MAIN DX HEATING COIL_UNIT1:Heating Coil Electricity Energy [J] (TimeStep) = 63176
• MAIN DX HEATING COIL_UNIT1:Heating Coil Defrost Electricity Energy [J] (TimeStep) = 26964

My Outputs

• MAIN DX HEATING COIL_UNIT1:Heating Coil Electricity Energy [J] (TimeStep) = 50499
• MAIN DX HEATING COIL_UNIT1:Heating Coil Defrost Electricity Energy [J] (TimeStep) = 27195

Thanks