This article is from the Piano Purchase and Maintenance FAQ, by Isako Hoshino rmmpfaq@yahoo.com with numerous contributions by others.
Pianos are very much like babies. Keep them out of drafts,
keep them out of direct sunlight. Basically, avoid any
extreme conditions (stay away from near the fire place,
etc.). It is also a good idea to keep sharp objects and wet
things (cups, potted plants) away as it can damage the
finish. Also keep them a couple of inches out from a wall to
prevent condensation behind it.
 
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