[time-nuts] Temp/Humidity control systems?
phk at phk.freebsd.dk
Thu Oct 27 09:28:43 EDT 2016
In message <20161027131226.0d5a72e62b2c91f2e13b637e at kinali.ch>, Attila Kinali w
>> Over insulating is a 100% sure-fire way to get unstable temperature inside,
>> because it amplifies the consequences of any change in power dissipation.
>> It is a classic mistake to build a 100mm insulated enclosure inside an
>> office-like enviroment and end up having less stable temperature on
>> the inside than the outside.
>No! Don't Stop! :-)
>That's why the next section I wrote described how to get rid of the
>excess heat in a controlled fashio. Of course, simply just insulating
>the room without giving it a lot of thermal mass or any form of control
>of the heat production/exchange will not stabilize the room.
Attila, I did read that.
You are right in a certain set of circumstances, for instance in a
already climate-regulated office space.
But your model is a recipe for grief and disaster if you do it in
a typical basement, on about 2/3 of the inhabited area of the planet
where you cannot ignore the humidity.
In general in a basement, it is a better idea to set up a closed
space and manage the humidity inside it, than it is to move the
humidity in and out of it.
WRT to humidity, that's a very unlinear relationship, but you can
get far by remembering these five rules:
* Warm air holds more *absolute* humidity (ie: g/m³) than colder air.
* At the same temperture, wetter air is lighter than dryer air.
* The temperature is never the same.
* Condensation should be avoided, period.
* You cannot "feel" absolute humidity, always measure it.
And yes, go ahead and look up number two, it's true. Dehumidifiers
belong on shelves under the ceiling, not on the floor.
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