Heat for the piano

[A440A@AOL.COM]

<<   a building that
will be unheated during the week, and they want to be sure that their
Yamaha P22 isn't damaged by the cold.
I never heard of any piano heater and told her that as far as I know she
doesn't need to worry that temperature swings will damage the piano.
Was I right? >>

Greetings, 
    My first reaction was to answer yes, no, maybe........  
   On second thought,  it occurs to me that that piano will never be in tune. 
 If you tune it cold, and they warm the place up fast, you could have 
condensation on the instrument, (as well as the pews, walls, windows, etc.) 
   To my own logic, (which is always open to question, so fire away.... when 
your brain is on fire, a little flaming feels like a cool spell !)  the speed 
of change has as much to do with destructive effects as the degree of change. 
 I have seen a guitar top craze when it was brought out of a cold car trunk 
and opened up in a very warm room.  How fast, and how differently are the 
back and front of that soundboard going to change?   
    My self-protective impulse is to tell them that stability will always be 
a problem, then tune it on an unheated day, with a nice well temperament, and 
let them get used to it.  
Regards,
Ed Foote