Climate Control Promotion

[Farrell]

I agree with you on the poor accuracy of cheap digital hygrometers. I've
been resisting spending $$ on a real one until I put my first board in a
piano. I have four of the little cheap ones from three different
manufacturers. They are all pretty close together except one of them. But
you are right, I will not know for sure unless I get a real one. Two are
from Damp-Chaser. I realize they are a decent sales tool, but why promote
them as a means to determine  RH in an environment?

Terry Farrell
Piano Tuning & Service
Tampa, Florida
mfarrel2@tampabay.rr.com

----- Original Message -----
From: "Delwin D Fandrich" <pianobuilders@olynet.com>
To: <pianotech@ptg.org>
Sent: Monday, January 15, 2001 3:35 PM
Subject: Re: Climate Control Promotion


>
> ----- Original Message -----
> From: "Farrell" <mfarrel2@tampabay.rr.com>
> To: <pianotech@ptg.org>
> Sent: January 15, 2001 10:28 AM
> Subject: Re: Climate Control Promotion
>
>
> > Hi John. I like the DC systems quite a bit, but I am disappointed on the
> > accuracy of their humidistats. Have you ever put the min/max hygrometer
> next
> > to the humidistat and checked it for a lengthy period of time (also good
> to
> > monitor room RH at the same time)? Also a good excercise is to plug an
old
> > electric clock (no digital) into the humidistat to see how long it runs
> over
> > a period of time.
> >
> > My own observations with many humidistats is that rather than turning on
> and
> > off within a few % of 42% RH, the regular calibration humidistats turn
on
> > and off in the 57% to 65% range. I wish I could keep my pianos in the
42%
> > range.
> >
> > Terry Farrell
> ---------------------------------------------------
>
> Terry,
>
> Have you checked the accuracy of your hygrometer? The most common type --
> i.e., those available through Pianotek, etc. -- are generally not all that
> accurate. Relative humidity is a very difficult thing to measure with any
> accuracy. It will cost you several hundreds of $$$ to get one that will
have
> certified accuracy much better than +/- 5% or so. I've checked a couple of
> the inexpensive digital hygrometers against my sling hygrometer and have
> found them to off as much as 20%.
>
> Still, while I trust the sling hygrometer, it is real difficult to get an
> accurate reading from it right up next to the soundboard.  So, I would
> suggest checking the digital against a sling from time to time and making
up
> a correction chart. While the inexpensive digitals may not be all that
> accurate, they do seem to be reasonably repeatable.
>
> Del
>
>