The defrost heater maka refrjiraeto tube dayameta nwere ike mere 6.5mm,8.0mm na 10.7mm, na tube ihe a ga-eji igwe anaghị agba nchara 304, ọzọ ihe nwekwara ike mere, dị ka SUS 304L, SUS310, SUS316, etc. The defrost okpomọkụ. ogologo na udi nwere ike ahaziri.