Dampp-Chaser wattage needed

Andrew and Rebeca Anderson anrebe at sbcglobal.net
Sat Oct 7 20:27:09 MDT 2006


Brett,
I service Steinways in several education institutions here with 
cooling systems that result in Rh readings from 60% and peaking to 
just over 80% most of the year.  I have a D in inventory that has 150 
watts under it.  50 watts are under the key-bed.  The system is not 
adequate.  We are going to add another 50 watts under the sound-board 
for a total of 200 watts and see how that does.

25 watts under a 7' grand is ridiculous.  Have you measured humidity 
there?  If tropical I'd start with 150 watts with one under the 
key-bed and the other two running down each side of the 
sound-board.  You probably want only a dehumidifier system and can 
centrally locate the humidistat.  Now a DC under the piano won't keep 
the environment well enough to control rust without a 
string-cover.  A wool felt cover will contain the environment above 
the board and extend it into the action cavity.  An undercover will 
help to stabilize as well.

Florida techs can probably share what they do to keep pianos rust 
free on the coast there.  What they do should work for you.

Andrew Anderson


At 05:25 PM 10/7/2006, you wrote:

>I'm interested in knowing how to determine the total or minimum 
>amount of heater bar watts are needed to install on any given piano 
>.  First a little background on why I'm asking .  I started 
>installing the full systems when I lived in the Mid-west . Now I'm 
>in Hawaii . When I got here I noticed that most if not all the 
>pianos I worked on had 25 watt  (or lower) bars in them with no 
>stats . The pianos were in bad shape;  rusted  & broken strings, 
>cracks, hammer felts coming off, etc. .  A lot of them were less 
>than 15 years old , and the ones that were closer to 25 years old 
>are now shot .  In most cases the cost of repairs is more than the 
>value of the piano . My thought was what a waste it was of the 
>instrument . And most of the customers didn't understand why I felt 
>humidity was the culprit when the dealers & techs in the area had 
>sold them a dehumidity system that was going to protect their 
>pianos.  I handled this as best possible for the first 4 years I was 
>out here, telling customers and dealers as the issue came up . Most 
>of the time it fell on deaf ears, and always with the dealers . They 
>said, "this is the way we have done it for over 25 years".  I can 
>see that . So I let it go until a new ( I won't say the model or 
>name brand but lets just say it was a 7' 6" grand ) got delivered to 
>Hana, one of the wettest and most humid areas on the island . One 
>thing I learned very quickly out here is that some areas are like  a 
>desert climate and others are like a rain forest - with everything 
>else in between. So when I first talked to the customer I asked if 
>he purchased a Dampp-Chaser system . More likely I knew from past 
>history with this dealer that a single low watt heater bar under 25 
>watts had been included and pitched as what the customer needed to 
>control humidity .  "Yes", he said, "and they said you would be 
>installing it" . So you can see where this is going . We now have a 
>dealer & a technician not on the same page, and looking very 
>unprofessional to the customer . So this all blew up on the 
>dealer.  Not what I wanted to happen,  but it's not like I didn't 
>try to prevent it .
>
>I called Dampp-Chaser after a somewhat  heated discussion with the 
>dealer, on his part telling me that I had to restate what I had told 
>the customer, because on the DC web site for techs, it states that 
>it is okay to use a 25 watt (or less) heater bar without a stat .  I 
>also talked with the piano manufacturers' service manager, whose 
>main concern was for the customer.  Mine too, as well as for the 
>piano!  I guess he thought I should have talked with the dealer 
>first.  I told him that I had, with no change in how they sold or 
>expected me to install the system.  He stated that they back the 
>systems as long as they were installed properly.  And then I asked, 
>"so what is a proper installation in your eyes?  He said, "You need 
>to talk to Dampp-Chaser."   They responded very quickly to an email 
>I sent them, and followed up with a phone call about my 
>problem.  After talking with them, they could not answer my question 
>either.  I got the old adage, "the piano will tell you If the pitch 
>is not stable".  I find it hard to believe that they don't have some 
>kind of an idea what minimum wattage would be required to keep the 
>soundboard at about 7% water content, and the piano at about 42% RH, 
>as I have read in their technical information.   It looks like they 
>have done their homework.  No, I know they have.  But I find it odd 
>they could not answer this question.  To me, adding a 25 watt (or 
>less) heater bar would be like installing an A/C system with a given 
>amount of cooling capacity(less than you would need at peak demand), 
>turned on high full time, and then expecting it to keep the 
>temperature the same as the sun comes up, or clouds and storms move 
>through.  The customer comes home and opens the house in the evening 
>to the nice trade wind ocean breezes, or starts a fire in the wood 
>burning stove.  Yes, we do have areas in the higher elevations up on 
>the volcanoes, where some of my customers have wood burning 
>stoves.  Granted, the drying effect would not be as great as in the 
>mid-west, where they are run for days at a time, but I would think 
>that a DC stat would turn off after a few hours if it was near that 
>stove.  So, is this a guessing game based on pianos we have serviced 
>over the years?  (25w, 35w, 50w, or a total on longer grands, where 
>I know they have found that more than one heater bar is 
>needed.)   In that case, it's always going to be over the 25 watt 
>level, which is why the dealer lost this round.  But what about the 
>other pianos out there?   I had let this run in the back of my mind 
>the past month or so, until a Chickering Grand showed up at my shop 
>yesterday that had been re-strung and worked over in the past.  It 
>had about 20 broken keys, brick hard newer hammers, and rust on all 
>of the strings . And guess what I found under the soundboard?  A 15 
>watt heater bar with no stat!
>
>I guess my real question is, why would anyone open the door for 
>people to be misguided by a statement on that web site, misuse the 
>product and, in my opinion, cause confusion that could lead to 
>damage of a customer's piano?  DC told me that for now it will stay 
>as stated.  I asked them if they could add a footnote that this will 
>not get the job done in most cases, however they would like to word 
>it.  I don't think they have ever done so.  The way they stated it 
>to me makes me think that there is more to this, maybe some kind of 
>a disagreement on this issue.  We all know how hard change is.  Or 
>maybe I'm wrong.  If so, please explain to me why.  I'm not one to 
>be told something is right without also being shown the facts to 
>back it up.  And the facts I have are that all of these pianos I'm 
>servicing over here are not protected at 25 or less watts with no 
>stat.  Any input on this situation would be greatly appreciated.
>
>Brett Glass
>
>A Sharp PIano Service, Maui
>
>
>--
>
>___________________________________________________
>Play 100s of games for FREE! <http://games.mail.com/>http://games.mail.com

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