<html> <body> Hi Barbara - Here are some of my useless suggestions: First, get yourself a good hygrometer.  I was using the "professional" one from Pianotek (#CMM880) which worked nicely until it stopped working.  I believe, however, that the specs Bob has in the catalog are not correct.  The company lists that unit as accurate +/- 5%, not 3%.  I (finally) replaced it with a somewhat better model (Mannix EP8706) which IS listed as +/- 3%, plus, it is "field calibratable", with the use of special salts.  All together with shipping it was around $170.  A lot, true, but then, instead of saying "It felt really dry",  you could say, "Yeah, it was 12%RH, (+ or - 3%) , and I'm sure of it because this thing here is really expensive".  Of course, you would have to remember to bring it with you.  While I haven't yet employed the undercover, I have not doubt that they can make some difference, however, I don't see how they, or Damppchasers themselves, can help the finish, the block, the bridges, or the action, when you have readings like 12%.  Maybe a vinyl cover, in conjunction with an  undercover would help.  Just out of curiosity, let me know how much the April-Aire system costs. Good luck - David Skolnik At 10:47 PM 2/16/2007, you wrote: <blockquote type=cite class=cite cite="">Howdy,   Hope you're all nice and cozy, it's been dang cold here.  I've got a question for you DC experts, I would have called DC themselves, but I didn't get home in time this afternoon.    Early this past fall I regulated a 1920s S&S A and installed a full DC system--but no undercover.  The piano is kept closed and covered when not in use.  The church has AC, though to me it felt humid  (for some reason I didn't have my hygrometer with me).   Anyway, before Christmas I tuned the piano again and it was 17 cents low.   Today I tuned it again and it was 14 cents low. Yikes.  The weather here lately has been extremely cold (OK, you nanooks of the north can laugh) and the church was incredibly dry--it didn't register on my not very good hygrometer.  A couple weeks ago, the music director called to tell me that tuning pins were slipping like crazy on the harpsichord I worked on last December.  I thought today that the tuning pins on the piano felt looser than in the past (or was it my imagination?).  AND I noticed that the regulation was off, too.  Geeze.  Apparently the heat is always on in the church--not one of those where it gets turned off and on, and it has felt warm to me the times I've been in there.   So...you get the picture that the place is dry.  Here is the question--how good a job should the DC system be doing in these circumstances?  Is anybody else experiencing this?  The music director said he is filling the DC tank at least once a week.  I even took a look to see if I had plugged things in the wrong place.  Is there anything else I can do, besides put an undercover on?  Can undercovers make a huge difference in a situation where there isn't significant air movement, etc?   I thought about recommending that the church look into a big April-Aire system.   Any suggestions are welcome.   Thanks.   Barbara Richmond, RPT near Peoria, Illinois </blockquote></body> </html>