[pianotech] Protection from underfloor heating

[Ron Nossaman]

On 12/11/2012 2:50 AM, David Boyce wrote:

>
> I was pondering the nature of the problem.  Why is it bad to have heat
> at the bottom of the piano?  Given that the underfloor heating won't be
> heating the room itself any hotter than any other heating system, and
> given that the floor does not get scalding hot, and given that wood is
> not a good conductor of heat, is it really so bad to have a warm-ish
> floor?  What does it do to the piano?

It's like a whole house Dampp-Chaser without the humidification. Or like 
radiators, with the piano directly above them. Convection keeps the 
piano immersed in warm air not only all the time the heat is on, but 
until the thermal mass of the floor cools, which will be in the spring 
when the heat is turned off. Forced air heat leaves the floor and the 
first foot of air above it cold, so you're not heating the piano as much 
or as constantly and cooking the moisture out of it. So the overall 
temperature isn't directly the problem, I think, it's the resulting MC 
of the wood in the piano.
Ron N