We have had a very humid and somewhat warmer climate in southeastern
Norway the last months.

The humidity is usually at 50-60% in the summer when it doesn't rain,
however it has been 70-75% most of the time, causing my Duo-Art piano
to be somewhat out of adjustment the last months.  It keeps well in
tune, but plays much more weakly than usual.  It is, however, not leaky;
I have the same resistance if I operate the pedals, it just won't play
very loudly.

I have also tried to move both the rods on the expression box down
manually, but it won't make the piano play very loudly.  It has
happened before during high humidity and has gone back to normal when
the humidity went normal, or a little dry (ca. 40-50%).  Earlier, the
piano has been louder (and tighter) at higher humidity levels, so I am
a bit confused.  Could this be something else?

It then seems that my piano is very sensitive to changes in humidity
(not so much the tuning, but as how the player mechanism reacts).
Since the humidity is very high, there are more insects than otherwise,
especially spiders, and I am concerned that those insects might build
nests or do something in the internal pneumatic parts, or perhaps feed
on the leather valves inside the piano.

Of course, the insects are not the same in the different states of the
U.S., and obviously, the types of insects are different in Europe too;
since I am no experts on bugs, I will have to try to describe these
small creatures as good as possible.

There are lots of spiders, and they are of the coin size, quickly
moving type, with hairy legs.  They seem to prefer certain corners in
some of the rooms in the first floor apartment which at the time, is
no good place for persons with arachnophobia!

They are pretty scary because they sometimes hide by standing
completely still on pretty exposed places, and if you get near that
place, they suddenly move quickly over the floor.

I haven't seen the spiders near the piano yet, however there is some
furniture near the piano that makes it difficult to be certain.

There are also sometimes very small (less than 1 mm) sized bugs that
have some kind of a shell; they are in theory small enough to crawl
inside the stack of the piano.  I haven't seen any insects in the
bottom of the piano yet, however I hesitate to give in for my paranoia,
and take out the stack to examine it further.

Occasionally one or two insects similar to a butterfly, with gray
wings, gets in through an open window.  They always fly towards the
light, and very often this happens unnoticed so they get trapped and
die.

I fear them most, since my lexicon describes moths as creatures that
are similar to butterflies, however I see them just occasionally when
a window  accidentally has been open when it is dark outside and the
lights are on inside.  Moths might feed on cloth, leather valves and
perhaps the pneumatics too.  I would believe that these insects only
lives in basements with much moisture, or what?

Since I see each type of insect only occasionally, with exception of
those quick moving spiders, I feel somewhat confident that my player
piano is safe, but I am not 100% sure since those insects hide behind
furniture, and in some of the corners (behind much furniture) in the
apartment.

Is there some way I can keep these insects out of the apartment to
ensure that the piano will be safe, or is it nothing to worry about?

We have electric heating cables in the floor here, which we hesitate
to use much in the summer time, as the electricity is expensive here
in Norway now.(*)

However, will it help to warm the floor somewhat?  Or will it harm
the piano, unless I warm the floor just a little?

(* Electricity expensive in Norway?  Doesn't Norway have cheap
hydroelectric power?  Well, our government sells as much of the
spare electricity to other countries around Norway, running the
water magazines lower than necessary.)

I am concerned about insects, since I once read a player piano horror
story in the MMD about a band organ or orchestrion that one season
wouldn't fire up because moths had eaten the leather on the inside.

And the climate in northern Europe really _is_ strange, since we have
had high humidity for several months here (and more intense rain when
it rains), and we live in the first floor, so the insects don't have
to try too hard to get in here.  A week ago, we actually have had an
extremely rare tropic (rotating) storm and some twisters here,
causing damage at an F2 level, luckily mostly north to Oslo.  The
meteorologists were confused, in opposition to those of us who have
seen many documentaries on the subject at "Discovery Channel."  :-) )

I know that low humidity might dry out the piano plate and make the
piano impossible to tune.  I also know that variation in humidity gets
the piano out of tune.

However, how about 70-75% humidity for some months, then perhaps 40%
humidity in the winter?  Is this variation too big for the piano?
Usually, the variations has been from 40-65%, something that seemed
to be barely acceptable.

What types of stores sell humidifiers and dehumidifiers, and what do
they cost?  There are very cheap humidifiers, that can be found at
flea markets, for virtually nothing; however I have been warned that
bacteria or fungus can grow in these one, so you have to buy a
high end humidifier to be sure.

Thomas Henden