Humidistat location in spinet

[Farrell]

Hi Clyde. Yup, it was me. Good question here. Your placement of the
humidistat will presumably result in rapid cycling of the unit. I should
think the possibility exists that the direct heat would turn the humidistat
off so fast that it would never allow the heat rod to lower the RH to the
desired level in most of the piano interior (I'm not saying I think it WILL
do that, but just suggesting the possibility). I think Dampp-Chaser's
suggestion of placing the unit "as high as possible but still under the key
bed", is so that it does not get direct immediate major heat from the rod,
but it will get indirect heat from it as it warms the whole interior of the
piano - close enough to be sure to react to the piano interior warming up,
but far enough away so that the warm piano interior turns the unit off, not
a direct blast of heat.

Consistent with this philosophy, I think it would be best to install the
humidistat on the side of the piano above the wooden support block for the
action support beam. If access was too difficult there, then below the
wooden support block. I think in this case, even hanging from the rod would
be better than three inches directly above the rod. I would just be afraid
of it shutting down immediately after the rod gets juice. You want the
humidistat to turn the heat off when the desired RH in the major portion of
the piano is reached - not when the humidistat gets a direct blast of heat
that may not have affected the rest of the piano interior.

All this, of course, is, IMHO.

Terry Farrell

----- Original Message -----
From: "Clyde Hollinger" <cedel@supernet.com>
To: <pianotech@ptg.org>
Sent: Thursday, August 16, 2001 7:41 AM
Subject: Humidistat location in spinet


> Friends,
>
> I believe it was Terry Farrell who mentioned that the humidistsat is NOT
> to hang from the heat rod in a vertical piano, if the humidifier is not
> part of the installation.  This quote is from the instructions that come
> from Dampp-Chaser with the humidistat:
>
> "3.  If a Humidifier is not included in the installation, attach the
> Humidistat to the side of the piano, as high as possible but still under
> the key bed with the screws provided.  It may be installed in a vertical
> position.  Steps 2, 4, and 6 are not necessary.  Installed in this
> location ensures that it receives feedback from the Dehumidifier and can
> react accordingly."
>
> Terry mentioned that he had never seen such an installation done by any
> other technician, so when I had one to install two days ago I determined
> to do it "correctly."  However, this piano was a spinet, with an action
> support beam well below the keybed and wooden support blocks on each
> side below the beam.  To mount the humidistat below all that would put
> it about half way between the keybed and the floor, which in my opinion
> was too low.
>
> I briefly considered hanging it from the heat bar as I had always done,
> but finally decided to screw it underneath the action support beam,
> facing down.  That puts it about three inches directly above where I
> located the dehumidifer.
>
> Questions:  Does anyone see a problem with what I did here?  The
> humidistat will certainly get feedback from the dehumidifier in that
> location.  I will be going back to tune the piano in four weeks and can
> make changes at that time if necessary.  Main question:  How much
> difference does the location of the humidistat make anyway, when
> installed in a small upright?  I tend to think that, while there may be
> some locations that would be totally inappropriate (the piano floor, for
> instance), there is a lot of latitude in where the thing can go and
> still have good results (assuming no water tank now).  Right or wrong?
>
> Regards,
> Clyde Hollinger, RPT
> Lititz, PA, USA
>
>