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Hi Everyone,<br>
<br>
I am working on the design of a small cleanroom facility (70m2) ISO
5/6. Right now, I am dealing with the problem of thermal load,<br>
Which is crucial here in Rio, where the average outside temperature
is of 30 deg C with a relative humidity of 75-80 %.<br>
<br>
I would like to have your help and/or comments on several points:<br>
<br>
Most of the manufacturers do not provide a value for the thermal
load (why?). Assuming 2 or max 3 people working simultaneously in
the cleanrooms, and usual cleanroom value: 22 deg C - 55% humidity.
The main issue is: how can I estimate the cooling power required for
the Air Conditioning System (ACS)?<br>
<br>
I have the list of equipments we'll have and the corresponding
electrical power. I assumed the heat generated by 2 users and added
the total electrical power dissipated as heat inside of the
cleanroom, using a simultaneity factor of 0.75 (all equipments won't
be turned on at the same time) and neglected the heat produced by
the filter fan and lightning. <br>
<b> </b><b><br>
</b><b> - Is it reasonable for dimensioning the ACS cooling
power ? </b><br>
<br>
Also most of the equipments have a cooling water circuit. But the
cooling power needed is well described in the installation manual
provided with the equipments. <br>
<br>
<b> - Should I subtract from the </b><b>ACS cooling power</b><b>
value, </b><b> the cooling po</b><b>wer </b><b>from the chillers?</b><br>
<br>
- <b>Do you think a central and unique chiller (placed
outside of the building) is preferred to several smaller chillers
placed closer to the equipment?</b><br>
<br>
<br>
I thank you very much for your kind help or comments.<br>
<br>
<br>
regards,<br>
<br>
Loïk.<br>
<br>
<pre class="moz-signature" cols="72">--
__________________________________________
Dr. Loïk Gence
PUC-RIO/CETUC-LABSEM
End Rua Marques de São Vicente, 225-Gavea
CEP:22451-900 Rio de Janeiro, RJ-Brasil
(Telefone) +55 (021) 3527-2193
(Mobile) +55 (021) 99156-5558
<a class="moz-txt-link-abbreviated" href="mailto:loik.gence@cetuc.puc-rio.br">loik.gence@cetuc.puc-rio.br</a>
__________________________________________</pre>
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