A. The manufacturer requires us to include this form with our shipment request so that they will have verification ("proof") on-file that they manufactured and shipped the correct heater." If you are ordering a 3-phase Eemax heater, you will need to print and fill out the appropriate order acknowledgment form (you can find the correct form below the ordering table for the model you want), and then fax or mail it to us. Eemax manufactures the 3-phase units to order, therefore, these heaters are not returnable.