A search of UL does not turn up any water heater manufacturers which resemble a AR company:
http://database.ul.com/cgi-bin/XYV/cgifind.new/LISEXT/1FRAME/srchres.html?begin=30&collection=/data3/verity_collections/lisext&vdkhome=/usr/app/verity_sw_rev24/common&query=KSDT%3CIN%3ECCN+and+not+GUIDEINFO&SORT_BY=textlines:asc,ccnshorttitle:asc http://goo.gl/lPtbZ T
