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<div class="moz-cite-prefix">On 9/25/2013 2:21 PM, Ross Elliott
wrote:<br>
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<p class="MsoPlainText">Does anyone know of an off-the-shelf
control system that would turn a ventilation fan on in a
greenhouse and dump warm air into a high-mass heat storage
room in winter / outside in summer? I want the fan to come on
whenever the temperature in the soap-bubble greenhouse is
warmer than the heat storage room, aka "the potting shed"
(although since it's a Steve Kohrner flying concrete design
it's more like a potting cathedral), so it’s not a fixed
temperature sort of setup, it depends on the temperature
difference between the two spaces.<o:p></o:p></p>
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Most solar controllers are differential based. You could probably
use one like that.<br>
<br>
Thank You Kindly,<br>
<br>
Corwyn / Topher<br>
<pre class="moz-signature" cols="72">--
Topher Belknap
Green Fret Consulting
Kermit didn't know the half of it...
<a class="moz-txt-link-freetext" href="http://www.GreenFret.com/">http://www.GreenFret.com/</a>
<a class="moz-txt-link-abbreviated" href="mailto:topher@greenfret.com">topher@greenfret.com</a>
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