"Peter Parry" wrote in message
...
On Sat, 23 Aug 2003 11:25:52 +0100, "IMM" wrote:


"Peter Parry" wrote in message
.. .
On Thu, 21 Aug 2003 17:03:30 +0100, "IMM" wrote:


Forced air and underfloor can mean the stat can be turned down a few
degrees. Both about the same.

On the contrary, to quote from http://meanradianttemperature.com/

"Good Thermal Design Tips (extract)

Use hydronic radiant floors

Heat people, not air"


Richard Kadulski wrote the following on MRT in the Renewable Energy
Policy Project :-

"A simple formula has been developed that allows normal comfort level
of a room to be calculated by adding the two primary heating
components: air temperature and mean radiant temperature (average
room surface temperature).

The formula is: air temperature ( F) + mean radiant
temperature ( F) = 140 ( F).

For example, with a conventional forced warm air heating system we
can maintain comfortable conditions at an air temperature of about 72
deg F (22 C) with a mean radiant temperature of 68 F (72 + 68 =
140).

With a radiant heating system, comfort is achieved at 68 F air
temperature if the mean radiant temperature is 72 F (68 + 72 = 140)".

With blown air systems the radiant temperature of all surfaces must
always be equal to or below the air temperature and for equivalent
levels of comfort higher, not lower, temperatures are required.

Kadulski, also wrote about comfort conditions, "While this may all seem like
much ado about nothing, it underlines that this fundamental idea is too
complex to define crisply with measurable numbers."






---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.507 / Virus Database: 304 - Release Date: 04/08/2003