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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Kamal,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Some years ago I ran into a similar situation of excessive humidity. The short version of the story was that during rainy conditions, the prefilters and filters
were getting wet, increasing the pressure drop across them, and increasing the suction (think vacuum) pressure of the fans between the fan and the filter, which was where the cooling coil resided. As a result, the cooling coil drain pan didn’t drain effectively
because the drip leg of the drain pan was not deep enough to overcome the negative pressure. This resulted in moisture re-entrainment and high humidity in the conditioned space. It was fixed by dropping the drain leg down a floor (14 feet) and increasing
its size one pipe diameter.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Tom Tribble<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> labnetwork-bounces@mtl.mit.edu [mailto:labnetwork-bounces@mtl.mit.edu]
<b>On Behalf Of </b>Kamal Yadav<br>
<b>Sent:</b> Thursday, July 23, 2015 9:42 AM<br>
<b>To:</b> labnetwork@mtl.mit.edu<br>
<b>Subject:</b> [labnetwork] High Humidity Issues in Coastal Areas?<o:p></o:p></span></p>
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<p class="MsoNormal">Dear All,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">During Monsoon time in India, and specially in Mumbai where it rains heavily from June to September, we observe high humidity in the lab ~65%. We have de-humidifiers as well as other HVAC infrastructure. But more control is required. Is
it possible or our infrastructure is not good enough?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Are there any other known humidity control solutions known to you. Is it the case with others as well, who are in heavy rains/humid area. This certainly is not the case with Intel in Portland, OR, where it rains a lot too.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Thanks,<o:p></o:p></p>
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<p class="MsoNormal">Kamal Yadav<o:p></o:p></p>
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<p class="MsoNormal">Sr. Process Technologist<o:p></o:p></p>
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<p class="MsoNormal">Electrical Engineering<o:p></o:p></p>
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<p class="MsoNormal">IIT Bombay<o:p></o:p></p>
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<p class="MsoNormal">Mobile: 7506144798<o:p></o:p></p>
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