Once a masonry heater builder friend turned to me in a test lab and said "Your problem, Jim, is that you're losing too much heat out of the front of the fireplace."
Duh. That's the whole point. But it's interesting that he saw this heat, lost into the room after all, as a "loss". It was just that much less heat that was available to be absorbed by the mass of the heater.
On a continuum, Rumfords radiate heat directly out of the fireplace opening far more efficiently than masonry heaters do and we "lose" about 20% of the available heat into the brickwork. At the other end of the continuum masonry heaters are far more efficient at absorbing heat into the mass to be used later and may "lose" about 20% of the available heat out through the doors.
So, Yes, you can use a heater as a fireplace but it's not a very good fireplace and you can try to use the heat absorbed into the bricks from a Rumford but a Rumford is not a very good masonry heater. Sometimes a combination sportscar/dumptruck just isn't a good idea.
Build one of each.
To: Jim Buckley
From: "Hallett, James"
Subject: Rumford/Masonry Heater
Jim - thanks for your insight - one last question - will a masonry heater function with the doors left open in warmer months if one just wishes to use it for ambience? - James
Buckley Rumford Fireplaces
Copyright 1996 - 2008 Jim Buckley
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