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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Hello CAUTs,<?xml:namespace prefix =
o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Last week piano technician John Ross
from </SPAN><?xml:namespace prefix = st1 ns =
"urn:schemas-microsoft-com:office:smarttags" /><st1:place><st1:City><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Windsor</SPAN></st1:City><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">, </SPAN><st1:State><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Nova
Scotia</SPAN></st1:State></st1:place><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> provided us with very useful
information that has helped us make progress on solving a minor, but persistent
quality problem associated with the H5 Humidistat in our Piano Life Saver
System.<SPAN style="mso-spacerun: yes"> </SPAN>The problem and our current
approach to eliminating it are detailed in the following
discussion.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">The challenge with a small
percentage of the H5s is that upon installation, the yellow low water warning
light works fine.<SPAN style="mso-spacerun: yes"> </SPAN>However, sometime
after installation, the yellow light fails and will not turn on when the water
in the Humidifier is low.<SPAN style="mso-spacerun: yes"> </SPAN>Usually,
this is discovered by the piano owner who calls the technician stating one of
the following two things, either<SPAN style="mso-spacerun: yes">
</SPAN>“It has been a long time and the yellow light has not come on to tell me
to add water.”<SPAN style="mso-spacerun: yes"> </SPAN>Or “the red light is
on and the yellow light has never come on”.<SPAN
style="mso-spacerun: yes"> </SPAN>The technician makes a service call and
finds the tank nearly dry in the first case and completely dry in the
second.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">John encountered this problem, and
happened to have two H5 Humidistats in his shop that he could use for the
replacement.<SPAN style="mso-spacerun: yes"> </SPAN>First, he decided to
test them in his shop and found that one of these failed within the three hours
time.<SPAN style="mso-spacerun: yes"> </SPAN>While this frequency of
occurrence far exceeds the rate we have seen in the field, the coincidence was
very fortunate as the information broke a technical impasse we were experiencing
in finding the root cause of the problem.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">John and I talked on the phone at
length about the issue.<SPAN style="mso-spacerun: yes"> </SPAN>He has had
some experience in electronics prior to becoming a piano technician.<SPAN
style="mso-spacerun: yes"> </SPAN>He thought there might be some sort of
thermal effect underlying the problem.<SPAN style="mso-spacerun: yes">
</SPAN>He suggested that proximity to a dehumidifier, as in a vertical
installation, might be providing heat to cause the problem.<SPAN
style="mso-spacerun: yes"> </SPAN>I explained that we had seen it in grand
pianos on occasion, where the Dehumidifiers are much farther from the
Humidistat.<SPAN style="mso-spacerun: yes"> </SPAN>The idea of temperature
being involved was new and kept me thinking.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">We set up tests where we sealed the
vent holes on the Humidistats and operated them overnight.<SPAN
style="mso-spacerun: yes"> </SPAN>Sealing the vent holes allowed for
excessive heat build up inside the Humidistat.<SPAN
style="mso-spacerun: yes"> </SPAN>The vent holes normally operate to
dissipate heat from the transformer on the circuit board inside the
Humidistat.<SPAN style="mso-spacerun: yes"> </SPAN>(The transformer was
added to the H5 to meet the increasingly stringent Underwriter’s Laboratory
<SPAN style="mso-spacerun: yes"> </SPAN>safety standards for our
product.)<SPAN style="mso-spacerun: yes"> </SPAN>However, the inside of
the Humidistat does get slightly warmer during operation.<SPAN
style="mso-spacerun: yes"> </SPAN>With the vent holes sealed, the inside
of the Humidistat reaches a much higher temperature than during normal
operation.<SPAN style="mso-spacerun: yes"> </SPAN>Using this procedure we
were able to duplicate the failure in a small number of Humidistats in our
in-house inventory.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I met with our design engineer,
Keith Howell, and our senior electronics technician, Randy Kaufman on
Friday.<SPAN style="mso-spacerun: yes"> </SPAN>Under microscopic
examination we had previously observed hairline cracks in a capacitor in the
yellow light circuit in units returned to us from the field.<SPAN
style="mso-spacerun: yes"> </SPAN>However, the cracks were found in
returns where we could not duplicate the problem as well as in units where we
could.<SPAN style="mso-spacerun: yes"> </SPAN>At our meeting on Friday we
agreed that the warming of the case during the first few hours of operation was
enough to widen such a crack and cause the circuit to fail.<SPAN
style="mso-spacerun: yes"> </SPAN>While this doesn’t tell us what is
causing the crack it gives us an excellent new approach to investigate this more
thoroughly.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Our next steps are as follows.<SPAN
style="mso-spacerun: yes"> </SPAN>We are testing all Humidistats under the
extreme condition of having the vent holes sealed during overnight
operation.<SPAN style="mso-spacerun: yes"> </SPAN>Failures are removed
from production and will be closely analyzed for why they failed.<SPAN
style="mso-spacerun: yes"> </SPAN>Gayle, our ten-year old son, Robbie and
I spent the weekend testing our entire inventory.<SPAN
style="mso-spacerun: yes"> </SPAN>Product shipped from our factory as of
Monday, April 28<SUP>th</SUP> will be free of this defect.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">We will begin testing bare circuit
boards while hot to see if we can reject them prior to assembly.<SPAN
style="mso-spacerun: yes"> </SPAN>If they fail under these conditions, it
will show that the cracking of the capacitor is being done by our circuit board
supplier.<SPAN style="mso-spacerun: yes"> </SPAN>If this is so we will
audit their factory to determine where in their process the problem is
caused.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">If it does not appear on the bare
boards, we will look even more closely at our process to see if there is
anything we are doing to cause a physical shock to the circuit board that could
create a hairline crack in the capacitor of concern.<SPAN
style="mso-spacerun: yes"> </SPAN>We have studied our process closely and
do not see anything of concern.<SPAN style="mso-spacerun: yes">
</SPAN>However, the recent thermal hypothesis and the use of heat in our testing
will finally allow us to make a definitive determination and move
forward.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">John has suggested that technicians
test Humidistats in their shops prior to installing the System.<SPAN
style="mso-spacerun: yes"> </SPAN>This seems like a prudent idea until old
inventory works its way through the distribution system.<SPAN
style="mso-spacerun: yes"> </SPAN>Simply place the Humidistat in an
upright position (vents facing upward as in normal installation).<SPAN
style="mso-spacerun: yes"> </SPAN>Plug in the two-light panel and let the
Humidistat run for a couple hours.<SPAN style="mso-spacerun: yes">
</SPAN>Contact us at 800-438-1524 if you encounter a problem and we will quickly
furnish a replacement.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I am grateful for John’s input to
the situation.<SPAN style="mso-spacerun: yes"> </SPAN>It really has made a
difference.<SPAN style="mso-spacerun: yes"> </SPAN>Thank you,
John.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">If any of you have encountered this
situation in the field, I apologize for the frustration you must have
experienced.<SPAN style="mso-spacerun: yes"> </SPAN>Also if you have a
return that you have not sent back to us, please do.<SPAN
style="mso-spacerun: yes"> </SPAN>It will help us solve this permanently
at its root cause, rather than eliminating the defect through testing at the end
of our assembly process.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I welcome your comments, concerns
and suggestions.<SPAN style="mso-spacerun: yes"> </SPAN>Please contact me
off the list at <A
href="mailto:roger@dampp-chaser.com">roger@dampp-chaser.com</A>.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Sincerely,<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Roger Wheelock,
VP<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Dampp-Chaser
Corporation<o:p></o:p></SPAN></P></DIV></BODY></HTML>