Dampp Chaser or not, that is that question!

[A440A@AOL.COM]

 John writes:

>The piano is now located in a room that the humidity swings from 60% to
>80%. On occasions it dips briefly to 50% on very 'dry' days.
>
>So my question to the list is do I:
>(a) install a DC de-humidifier (tropical version which is set at 55% or
>so I believe), or
>(b) because the piano has lived in a high humidity environment all its
>life and settled into that groove just leave it alone.

Greetings, 
    Was the piano stable?  did the tuning vary with the seasons? How much? 
I would, just on first reading, suggest that you not worry about the climate 
control.  If it is only swinging from 60 to 80% I don't think a control 
system is going to make a big improvement.  If the strings are rusty, a 
string cover would be a good idea on the new set.  How tight are the pins? 
Over 140 in/lbs?
Regards,
Ed Foote