<oembed><type>rich</type><version>1.0</version><title>Bill Cypher wrote</title><author_name>Bill Cypher (npub1qy…dmu7u)</author_name><author_url>https://nostr.now/npub1qyxlpj2gl6dt2nfvkl4yyrl6pr2hjkycrdh2dr5r42n7ktwn7pdqrdmu7u</author_url><provider_name>njump</provider_name><provider_url>https://nostr.now</provider_url><html>Heat from a fire is actually 3 things. The air that has been warmed by the fire, the infrared light coming off the fire, and the thermal mass of all the masonry that gets heated. &#xA;&#xA;The air does mostly go up the chimney, of course because otherwise your room would fill with smoke. The infrared and thermal mass are where you make your gains. &#xA;&#xA;There are also losses from sucking cold outside air into your home. This matters in a newer airtight home where you have to crack a window for your chimney to even work. On a drafty older home air was coming in anyway so not as big a tradeoff. </html></oembed>