239 volts, single phase, 15KW load, equates to 69.7 amps of load. That (69.7) is approx.
If that is the case, the breakers should trip before they melt unless they are junk breakers to start.
Mike, per code, a 15k heating load is considered a continious load which requires a 125 demand factor. Per 15k heater requires a minimum of an 80 amp breaker (15,000/240x1.25= 78.125). However, 424.22(B) limits the OCPD to 60 amps. Is it possible to split up the loads to keep load to 11.5K per cicuit so the OCPDs are at 60 amps or less? What are they heating with such a big heater?
