Does max efficiency equal max heat?

No, not necessarily. Vent free appliances utilize the oxygen in the room to function. Therefore, in order to maintain safety, vent free heating appliances are rated at very low BTU/heat amounts. For example, a typical vent free burner system at the 18” size will be rated at 30k BTUs. However, a vented H-burner at the same 18” size, is rated at 155k BTUs. That is a little over 5 times more heat potential! Even if you were to lose half of that heat (in this example), due to the draft of the vent or chimney, you would still be receiving well over double the amount of heat you could expect from a vent free heating appliance.


Emily Lozano