<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; = charset=iso-8859-1"> <META content="MSHTML 6.00.2600.0" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY> <DIV><FONT color=#800000>Comments interspersed below:</FONT></DIV> <DIV><FONT color=#800000></FONT> </DIV> <DIV><FONT color=#800000>Terry Farrell</FONT></DIV> <DIV> <SPAN id=__#Ath#SignaturePos__></SPAN> </DIV> <DIV>----- Original Message ----- <DIV>From: "Isaac OLEG" <<A href="mailto:oleg-i@wanadoo.fr">oleg-i@wanadoo.fr</A>></DIV> <DIV>To: <<A = href="mailto:pianotech@ptg.org">pianotech@ptg.org</A>></DIV> <DIV>Sent: Tuesday, July 30, 2002 8:06 AM</DIV> <DIV>Subject: RE: DC Study - was Another heater bar without a control...</DIV></DIV> <DIV><BR></DIV> <DIV>> I believe that any DC system installed may be well dimensioned = in<BR>> regard of the conditions of the room, the piano type, = etc.<BR>> <BR>> I have a very precise electronic R.H. tester (0.1 %precision with<BR>> external gauge) and I remember that I checked a simple 30W = element in<BR>> a little Yamaha 108 vertical, that I installed in a very = moist place<BR>> under the house.</DIV> <DIV> </DIV> <DIV><FONT color=#800000>I'm having trouble picturing this. Was the DC = bar, or the piano installed under the house? I know I've gotta be missing = something here.</FONT><BR> <BR>> I came back 1 month later and checked = inside the piano and in the<BR>> room. The heater was permanent for this test, = and , probably because<BR>> no air flow in the piano and not enough power, = the R.H level was AT<BR>> THIS TIME higher in the piano than in the room (63% = in the piano while<BR>> 58% in the room if I remember correctly).<BR>> I = was very surprised, but I believe it was only because the room had<BR>> been = opened, or it was in a more dry time, and the piano did not have<BR>> enough = time yet to stabilize to the dryer climate. But it was evident<BR>> then than = the heater element was not strong enough for this case.<BR>> <BR>> Of = course that does not mean the system, if correctly dimensioned,<BR>> would = not work, but if the humidity is too high, having not enough<BR>> heat in the dehumidifiers will may be create more hot warm air than<BR>> dry = one.</DIV> <DIV> </DIV> <DIV><FONT color=#800000>Hmmmmm.</FONT></DIV> <DIV><BR>> I believe too that there may be a relation with the flow = of air, if<BR>> the same air is recycled always in a somewhat close = environment, I<BR>> can't see how the moisture can go out. It have to swell thru the<BR>> parts, the felts, the case, so may not it be necessary to = have some<BR>> apertures to allow for air circulation ? (not sure at this one)<BR></DIV> <DIV><FONT color=#800000>If the piano had equilibrated with the room = humidity, no. If, by chance, the piano was very moist (left out in the rain?), = then yes, I would indeed benefit to have some air circulation. But under normal circumstances, no.</FONT></DIV> <DIV> <BR>> I installed recently a 3 bars system in a 68% place = under a little<BR>> grand, and indeed 1 hour after plug in, there was a nice = 43% place<BR>> just under the soundboard<BR>> <BR>> A chart with information on how much temp/R.H may relate with how much<BR>> power = (in Watt) could be very helpful for choosing components.<BR>> <BR>> = Any thoughts ?</DIV> <DIV><BR><FONT color=#800000>You bet! Plug an old-type mechanical = clock into the humidistat along with the heater bars. Observe the clock over time to = see how long the system has been running. With the room near the maximum = humidity range, make sure the DC system shuts off once in a while. That way you = know you have just enough power to maintain RH at whatever the shut-off point of = the humidistat is.</FONT></DIV> <DIV> <BR>> Regards.<BR>> <BR>> Isaac OLEG<BR>> = France<BR>> Well tempered climate (not tuning!)<BR>> <BR>> > -----Message d'origine-----<BR>> > De : <A href="mailto:owner-pianotech@ptg.org">owner-pianotech@ptg.org</A><BR>&g= t; > [mailto:owner-pianotech@ptg.org]De la part<BR>> > de G = GRAVINA<BR>> > Envoye : mardi 30 juillet 2002 12:45<BR>> > A : <A href="mailto:pianotech@ptg.org">pianotech@ptg.org</A><BR>> > = Objet : DC Study - was Another heater bar without a control...<BR>> ><BR>> = ><BR>> > Matt W wrote:<BR>> ><BR>> > >I would be = willing to participate in data collection with you<BR>> > >Jerry.  = Although I sound pretty biased against this<BR>> > hardware,  = I can be at<BR>> > >once skeptical and at the same time = open-minded.  In my<BR>> > opinion, any study<BR>> > >should involve at = least one pair of pianos - one for the<BR>> > hardware and an<BR>> > >"untreated" piano as a control.  The pianos should also = be<BR>> > left untouched,<BR>> > >so as to avoid any data contamination = through tampering.<BR>> > Unfortunately, I<BR>> > >don't know of = anywhere where this condition exists, except<BR>> > maybe for a<BR>> = > >store with a storage facility, which might involve rental<BR>> = > and storage fees.<BR>> > ><BR>> > >Gotta keep it interesting<BR>> > ><BR>> > >Matt<BR>> ><BR>> = > Folks,<BR>> ><BR>> > If one were to set up such a study, = what other parameters,<BR>> > controls,<BR>> > frequency of data = collection, length of study, etc., should<BR>> > be considered?<BR>> = ><BR>> > Jerry Gravina, RPT<BR>> > Babylon, NY<BR>> ><BR>> ><BR>> </DIV></BODY></HTML>