<html> <body> Hi Bob,                With -30C air coming into the building during Jan.each piano should have 2 damp chasers. But this is the reality of budgets. I have a lot of data that I am sorting through. Things are not what we assume. So many variables.  Water supplies, electrolytes, Efficiency of pads vs time, Frequency of door's opening (draft)  Positioning of measuring device, and so the list goes on. Trying to get into the 40% range is one thing, keeping it there is another story altogether.  That's why measurements are made 24/7 every 15mins. At 09:16 PM 5/23/2006, you wrote: <blockquote type=cite class=cite cite="">Roger, Why are these humidity levels not closer to the 45% area?  Is this not what the systems are supposed to accomplish?  Have I misunderstood? Bob Hull --- Roger Jolly <roger.j@sasktel.net> wrote: > Hi Stan. >                 I think the results of the data > loggers show a lot.    This > graph is a sample of two closely matched C3 grands > in a teaching studio at > the University. The pianos sit side by side . Both > pianos had calibrated > data  loggers fixed in identical positions on the > centre beam. > Humidity and temperature measurements were made > every 15mins 24/7. > One piano with cover, one without. > The covered piano had the damp chaser unplugged for > a few days. > Tuning changes were also made on a weekly basis, but > I will share that data > at a later date. > You will note that the temperature of the covered > piano is one to two > degrees higher because of reduced circulation, but > the humidity is on > average 10% higher. > My research has shown that pads should be changed > every 60days for maximum > efficiency. > > Just some teaser information. > > I will get around to collating and publishing more > extensive data later. > > Point.  These bottom covers work, now we have to > collectively find better > ways to install them. > > Regards Roger > > > __________________________________________________ Do You Yahoo!? Tired of spam?  Yahoo! Mail has the best spam protection around <a href="http://mail.yahoo.com/" eudora="autourl"> http://mail.yahoo.com</a> </blockquote></body> </html>