<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body bgcolor="#ffffff" text="#000000"> If I have even a glimpse of how this works, infrared is a form of light, and when it shines on a mass, the mass gets warmer. That's why my masonry stove can heat me while the air is still not all that warm. And I think that's why the bakeoven (which is the firebox, but after a fire is finished) does such a great job of cooking: it heats whatever you put into it in three ways: by contact with the floor of the oven, by convection around the container, and by radiation in the infrared, from the firebrick floor, sides, and top. It's been awhile since I studied this, but I do know that sitting in a room with hot soapstone panels radiating into it is more satisfying than heating the air and sending it through floor vents. Susan Kline Dean May wrote: <blockquote cite="mid:2AA657FF74954CFCB7EA16799BD8EE19@ToshibaNetbook" type="cite"> <pre wrap="">The air in the thermals of which you speak is not heated by radiant heat. If air was significantly heated by radiant heat than the upper atmosphere would be very warm, not cold. The radiant heat of the sun heats the mass of the earth, and that is what heats the air and creates the thermals. I have hot water heat, and while it is true, they are designed to heat air by convection, it is also true that a 72 degree room with cast iron hot water radiators feels warmer than a 72 degree room heated by forced air. The cast iron at 95-135 degrees radiates a lot of warmth that is not transmitted by the air. Dean Dean W May (812) 235-5272 voice and text PianoRebuilders.com (888) DEAN-MAY Terre Haute IN 47802 -----Original Message----- From: <a class="moz-txt-link-abbreviated" href="mailto:pianotech-bounces@ptg.org">pianotech-bounces@ptg.org</a> [<a class="moz-txt-link-freetext" href="mailto:pianotech-bounces@ptg.org">mailto:pianotech-bounces@ptg.org</a>] On Behalf Of Ron Nossaman Sent: Tuesday, December 11, 2012 9:59 AM To: <a class="moz-txt-link-abbreviated" href="mailto:pianotech@ptg.org">pianotech@ptg.org</a> Subject: Re: [pianotech] Protection from underfloor heating On 12/11/2012 8:40 AM, Dean May wrote: </pre> <blockquote type="cite"> <pre wrap="">Radiant heat works not by warming the air, though there is some of that, </pre> </blockquote> <pre wrap="">but </pre> <blockquote type="cite"> <pre wrap="">by radiating the heat, duh. ;-) </pre> </blockquote> <pre wrap=""> It's misnamed. It's only radiant to a small degree (sorry). It primarily warms the air, like a radiator (also misnamed) which circulates by convection. The radiator, granted radiates much more because it operates at a much higher temperature. </pre> <blockquote type="cite"> <pre wrap="">Objects with mass in view of the radiant heat source absorb the heat and began to warm in temperature. The closer </pre> </blockquote> <pre wrap="">the </pre> <blockquote type="cite"> <pre wrap="">object to the source, the more heat is absorbed. A piano with lots of mass sitting very close to the source will absorb lots of heat. While air, with negligible mass, will not absorb much heat. So measuring the air's temperature will not be any kind of indicator as to how much heat the </pre> </blockquote> <pre wrap="">piano </pre> <blockquote type="cite"> <pre wrap="">is getting. </pre> </blockquote> <pre wrap=""> Talk to desert glider pilots and buzzards about thermals some day. Ron N ----- No virus found in this message. Checked by AVG - <a class="moz-txt-link-abbreviated" href="http://www.avg.com">www.avg.com</a> Version: 2012.0.2221 / Virus Database: 2634/5451 - Release Date: 12/11/12 </pre> </blockquote> </body> </html>