Ray Finch asked, in 010907 MMDigest:

> I know that pianos don't like excessive heat (pneumatic coverings
> crack, rubber tubing and leathers dry out, etc.), but what damage
> does cold do to a player piano?

It would depend on how much cold.  Much below freezing would cause
separation and weakening of glue joints etc, but temperatures around
or above freezing would cause very little damage, though it would be
better not to play the instrument at that temperature.  We sometimes
take organs out in the winter, provided the temp is just above
freezing, and have experienced no problems with them.

Damp is far worse than cold, and so is heat!  In general, wood and
leather are far more affected by humidity than temperature.

David Evans
Mechanical musical instrument restorer