Answer to Question #123614 in Classical Mechanics for adam stuart

Question

Hi:

Outdoor pool motor enclosed in a waterproof wood box, one ventilation vent with fixed louvers on each wall of the box. Temperature exceeds 250 degrees F with the box fully closed and at some point thermal protection breaker shuts down the motor until temperature drops. Installed 18V (0.3A) solar powered PC fan on each wall (20W solar panel for each).. Scientific American thermometer is used to record temperature inside the enclosure. Question: trying to maximize removal of the heat generated by pump motor. Should each PC fan face outward (exhaust the heat)? One fan face outward, and the other face inward (one fan draws cooler air into the box, the other continues to exhaust the heat?) Flooding conditions in Florida required me to design a waterproof enclosure but the heat that builds is enough to trip the thermal breaker. Could not raise the pool motor concrete pad so had to design an enclosure.

Thank you.

Answer 1

Hello. Yes, the best option is to use one fan on the inlet and the other fan on the outlet. The first fan delivers the air into the enclosure, the other one removes the hot air. Make sure that the air flow passes the hottest elements. Additionally, you may consider installing a separate fan on the breaker. This will provide the most efficient removal of hot air. 

The other option is to choose a thermal protection breaker of a higher temperature rating.