Howdy -- At this time of year, the piano becomes a little loose due
to the inside air only being 25-35% humidity.  As my electric bill
essentially doubled last month (utility price hike 2x), leaving the
heat up at all times to stabilize the humidity is not an option. In
fact, an automatic set-back thermostat on the heat-pump is used for
off-hours set-back.

There's another problem which I'm experiencing with low humidity.  Some
notes didn't seem as strong as others, so when I took a look today I
noticed that some of the hammers were only striking two of their three
strings.  The butt flange screws had become loose, allowing the hammers
to sway.  Tightening solves the problem, but may cause another problem
when the 80%-90% relative humidity of summer returns and stresses these
screw holes.

According to the MMD Archives, the Steinway people say 68-72 degrees F.,
at 40-60% humidity, is required to be compliant with their guarantee.
Wow -- I can just picture my electric meter grinning if I tried that!

The Archives offered little of how to actually get the humidity into
the piano.  After disastrous results on his house while using a
humidifier, Bruce Clark said he used quart containers of water with
home-made wicks that were spaced on either side of the piano's sound
board.

On a player, the air in the cavity is exchanged throughout the
exhausting action of the bellows, so you're essentially administering
humidity shocks to the instrument each time you use it.  Does anyone
feel that this water-wick method is particularly harmful in any way?
E.g., would I accelerate any rusting?

Karl Ellison
Salem, Massachusetts  U.S.A.