FWD: Is complete 5-Part Dampp-chaser unit always necessary?

[larudee@pacbell.net]

Ryan,

I definitely like the two-part system (humidistat and rod(s)for climates
where low humidity does not
occur.  It is not only less costly and maintenance free, but you also
don't need
as much drying power because you don't have a tank of water to deal
with.  I
like to use the least powerful system that I can get away with, which is
to say
that when the ambient humidity is at its highest, the dehumidifier will
be on
most of the time.  I prefer this because it results in less and slower
cycling,
i.e. when the heat goes on, it tends to stay on for a longer time.  I
find that
this gives greater stability to the system because it is not changing
from one
state to another as frequently.  Lower wattage also reduces the risk of
heat
expanding parts of the plate or the strings in some uprights.  Here in
the San
Francisco Bay area, where the humidity is usually between 40% and 75%, I
find
that 25W is usually enough for spinets and consoles, 35W for larger
uprights,
50W for small grands, 75W-88W for larger grands and 113W-126W for
concert
grands.

I find that pianos with this system are more in tune after a year than
pianos
without it are after six months.  The caveat that I always tell my
customers,
however, is that they are not allowed to move the piano to a different
climate.
If they do, the system may not work as well unless modified to a full
system.

I can understand Dampp-Chaser not being enthusiastic about this
practice,
because the piano could get sold and moved to another location and the
system
would no longer function properly, in which case the new owner might
blame the
manufacturer.  For most of my customers, however, I think the partial
system is
in their best interest, as long as they are fully informed.

Paul Larudee

Jeannie Grassi wrote:

> Dear List,
> This came to me for your consideration from Ryan Sowers, RPT:
>
> >>As technicians we try to educate our clients so that they can take the
> best
> care of their pianos. I have attended several classes on humidity control at
> conventions and talked with experienced technicians whose opinions I
> respect. Combined with my a bit of personal experience with these systems I
> have become convinced that they are of substantial enough benefit that we
> are doing our clients a disservice if we are not actively promoting these
> products. However there is an aspect of humidity control that I do not
> understand.  Is the humidifier component beneficial in environments where
> the relative humidity never drops below 42%? Since the humidifier is the
> most expensive portion of the system and also the only part that requires
> routine maintenance it is tempting to recommend installing the dehumidifier
> and the humidistat only.  I called dampp-chaser and asked them if they had
> studied the effectiveness this and they said no and that the only system
> they recommend is the complete system. Here in the Pacific Northwest the
> indoor humidity practically never goes below 42 % except in cases where the
> client has wood heat. I believe in the value of humidity control, but am I
> wasting my client's money recommending the 5 part system when a simple 2
> part system might be as effective?
>
> Sincerely,
> Ryan Sowers RPT
> Puget Sound Chapter<<
>
> Jeannie Grassi, RPT
> Associate Editor, Piano Technicians Journal
> mailto:jgrassi@silverlink.net