Pipe Organ Pitch Variation

[PDtek@AOL.COM]

It is common knowledge that the pitch of a pipe organ varies with room
temperature, but just how much?

Occasionally I will be asked to tune a church piano with the pipe organ when
the sanctuary is much cooler than it will be on performance day. I check the
organ and it is off pitch. The question is, is there some formula that will
tell me where the organ pitch will be at normal room temperature. In other
words, if the room will be 10 degrees warmer when the piano and organ will be
played together, how much will the pitch change?

Dave Bunch