Review on Natural Gas Heater: Mr. Heater Vent-Free 20,000 BTU Blue Flame - Multi-Size Option by Doug Hammett

attempted to carefully place the included silver connector to bottom of unit. would not thread properly at all. when trying to remove it, was extremely difficult to remove, completely destroyed the threads on the connector, (it was so damaged, it looked as if the threads had melted), and damaged the threads inside the bottom of the unit. attempted to clean threads in bottom of unit. will need to get different sized tap wrench and if that is not successful, will either have to have part replaced or get another unit. this is my third ventless gas heater, (one was a Mr. Heater and the other a Dyna-Glo), and didn't have any problem whatsoever with the other two.