I manufacture heating elements and a customer wired a delta heater in parallel with a wye heater. They claim that this lowers the overall resistance of the delta thus causing this element to draw more amps than what it was designed for. I disagree and do not see how the heater is eternally wired would make any difference and that each element will draw the appropriate amperage. Line current into the delta heater will be higher than the actual phase current in the heater itself but combining the two types of configurations in parallel should not cause a problem. I am just looking for some re-assurance.