He did not mean your stove Don... He meant the US Stove, its rated at 50,000 and if I remember. You were the one who pointed out, that its minimum feed rate is 5 lbs an hour. He was not stating every 50,000 BTU stove. Mine is 47,500 also and its max is 5.5 lbs an hr. Both of our stoves "Are" efficient. The US Furnace in question is not.