This is a piece of junk. There is hardly any insulation around tub.  I have owned 5 tubs and have never seen this poor of quality.  It has been running over 24 hours and is only at 91 degrees.  The outside temp average is about 65.   The service door has vents in it and across from that door is the fiberglass tub with NO insulation.  In Illinois it will not hold its temp at all like that.  Gonna return it.  Junk!!!