Hi All,  At the risk of sounding redundant, controlling the
"environment", not the instrument, is the key to longevity and
tuning stability.  I've personally seen more damage than good when
a well-meaning (or perhaps not so well-meaning) technician installed
a system for controlling temperature and humidity 'inside' of the
piano (or player piano).

However, there are two other factors that are commonly overlooked.
They are sunlight and wind.  While these two environmental factors may
be important for plants, they can be devastating to pianos.  Pianos
should never 'see' direct sunlight, and they should never be placed
"in the path of moving air".

I want to echo Jonathan Holmes comments yesterday.  Stability is very
important.  Even if the environmental factors are slightly outside of
the 'desirable' range, it's the fluctuations that are hardest on older
instruments.

The fact is, we, as tuners and technicians, have no control over the
environment.  However, you can't blame the owner if they've never been
educated about the facts.  On the other side of the coin, if they have
been educated, and chosen, for whatever reason, to ignore the facts,
the tuner/technician should just keep taking their money and doing the
best job he can.

On a personal note, nothing is more depressing than going back to an
instrument that I've totally restored only to find one side of the
piano bleached out by sunlight, rusty strings and mildew on action
parts from too much moisture, and spider webs and felt mite infestation
caused by poor housekeeping.

Although not necessarily the best analogy, it reminds me of a comment
that my 93-year old mentor told me in the early 1970's.  About piano
tuning, he said, "Tell them it's a tuning hammer, not a magic wand."

Musically,

John A. Tuttle