[CAUT] Re: Temperature/Humidity

[James Ellis]

Chris, 

It's a problem that just won't go away.  Summer and winter present opposite
problems, depending upon the climate where you live.  The basic thing to
remember is:  Warm air holds more moisture than cold air, and it's relative
(not absolute) humidity we are concerned about.  I HATE putting stuff in,
or under, pianos - heaters, water buckets, wicks, etc.  But then there are
times when it is the lesser of the evils.  I much prefer controlling the
piano's environment.  

But then, Don makes a good point too.  Vapor barriers in walls aren't the
last word either, and condensation inside the walls can be a big problem.
Moisture just goes right through a wall if there is no barrier.  But if
there is a barrier in the wall, it and the insulation must be done just
right, or else the moisture will condense inside the wall and cause rot and
mold.

Your data logger is to be believed over your client's windows that "sweat".
 What his windoes do depends not only upon what the inside relative
humidity is, but upon what the outside temperature is, what type windows he
has, and what temperature the inside surface of the glass is - vs - the
temperature of the inside air.  He probably has the right idea, but the
wrong answer.  

I think Don is right.  As much as I hate to put foreign objects into or
under pianos, this might be a case where your client needs a complete
system installed in his piano.

Jim Ellis