Basically, you can only convert ton to Killowatt cooling capacity and this cannot be use in electrical calculatio. What most HVAC designers do is to get a catalogue/ technical brochures and select an available units then from their you can see the Electrical Power input required by the Unit.
If you have more questions that you think I can help, please email me to my email address below because I have not internet connections at my office.
3. Remember that this tells you the heat load not the electrical power required; the electrical power requires a knowledge of the efficiency of the unit under operating conditions.
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"Well, I've wrestled with reality for 35 years, Doctor, and I'm happy to state I finally won out over it." Elwood P. Dowd