Euromax Output -36700 btu ????

[homeskillet]

Please help me understand something. The Euromax claims to have a 70,500 btu input. When you look at their webpage, under specs, its states the "overall heat output range is from 8300 btu to 36700 btu". I called the the manufacturer and he stated.....yup....they put out 36700 btu. That means in the end, the Euromax is only 52% efficient in the real world. A lot of stoves take a lot less than 70500 btu input to get 36700 btu output. Can someone help me out (the company couldn't). Can I only expect 36700 btu out of this stove. Based on those figures....this stove is a waste of money (and pellets).. Please help clear this up