Hi JIm, Deb and list, I've been following the Dampp-Chaser thread with some interest (as the Australian Distributor). To answer your point about the system switching in at odd times......the system is never actually off at any time, it switches from humidifying (up to 50%) to dehumidifying (down to 38%) and back. This is more reliable, efficient and produces best test results. If it switched on and off it would be very prone to short cycling (on and off again in very short bursts) electrically this is not good and doesn't make for good reliable mechanisms over the long term. In climatic conditions that are dry the dehumidifying cycle tends to be very short with longer humidifying cycles and vice versa. Many techs make this mistake, particularly when the customer questions why the system is in the "wrong" cycle for the prevailing conditions ie the rod is on and it's 90 degrees F and 25%RH. It's just doing it's job getting the system back towards the _average_ 42% the system is aiming for. A similar misunderstanding-type problem can develop when there is not sufficient dehumidifying power in the system. A system with a 25watt or worse a 15watt rod to keep the piano (vertical) under control in an environment that gets to over 80% RH is asking for trouble. The system never switches over, and customers with a new system are constantly checking to see if it has switched over (notice that I never say it switches off?) The rule of thumb in an upright (vertical) is that you need 1 watt of power to reduce the RH by 1%. So if you want the system to cope with an environment that gets over 80% RH you need a rod that is more than 35 watts. The lesson here is .......Don't generalise! Take a Hygrometer and see what is actually happening in this customer's very specific and sometimes unique situation! I must ask Bob or Gayle Mair if there is a similar rule for grands. Does anyone else know? The underside covers that are being developed at the moment sound pretty cool (sorry pun was irresistible) too. The grands will be far less prone to drafts and heating ducts etc. Keep an eye out for them. Hope I've been clear enough.....it's getting late here. Goodnight Mark Bolsius Canberra Australia Jim Harvey wrote...... Case #3 - complete CC system: My piano, my living room in Pasadena. I installed the system to see the results for myself. In addition to the low-water light (all there was at the time), I added an additional box under the keybed with two indicator lights. One was wired to the humidifier, the other to the dehumidifier. Since one or the other would always be on, I always had visual verification that the system was plugged in. Two interesting observations came from this experiment: - during Santa Ana conditions, I had to fill the water reservoir once a week. I could understand this in a grand, but this was a console piano. - at other times, I noticed the humidifier (and light) would come on during strange times, like 2:00am when things were calm and cool. I asked (Allen Foote at the time) about this. He suggested that, like a frying pan, the plate was warming up during the day. At night, the plate was returning that collected heat back into the piano. This in turn had a drying effect (mini Santa Ana) inside the piano, so the humidifier portion kicked in. I don't really know if the last example represents what's actually happening. Regardless, I came to trust the Humidistat to know what it was doing -- whether when or why. Sorry I couldn't answer your questions. I'd almost bet DC has some statistics on "out-of-control" heater rods -- they have stats on just about everything. Now, get back to your reports! <g> At 10:28 PM 4/6/99 -0400, you wrote: >In a message dated 99-04-06 20:33:17 EDT, you write: > ><< Invariably, the client has moved from a location that this installation >actually worked! In some cases, the piano could possibly have used a higher >wattage unit or > multiple rods... still without the need for a Humidistat. >> > >Hi, Jim: > >Couldn't resist responding to this - although it may not be my best way to >jump back into the fray during a short break from making reports to my >schools. I still have a hard time with a Dampp-Chaser (Dampp-Chaser, >Dampp-Chaser - practice makes perfect) humidifier without a humidistat. A >few times that I serviced pianos right after they came from Hawaii to So. >Calif., when they had little time to dry out - and they were already dried >out! Loose pins, actions, etc etc. > >Still, you have seen a lot more of these situations than me - still in place >in a humid climate. What do you speculate the average RH is inside a >vertical piano with a heater bar ( always on? > >Bill Shull >University of Redlands, La Sierra University >BDShull@aol.com > Jim Harvey, RPT Greenwood, SC harvey@greenwood.net ________________________ Redmond, WA -- Microsoft announced today that the official release date for the new operating system "Windows 2000" will be delayed until the second quarter of 1901. -From Penny Pennington (p2)
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