A/C Condenser Evaporative Cooling Assist

pianotuna wrote:

dclark1946 wrote:

I thought you were referring to the rooftop RV evaporative cooler where you would keep a window open for proper operation. The reason your cooler did not work is because it kept raising the interior humidity level to the point that very little evaporative cooling could occur. These coolers only work when you have a continued fresh supply of outside air.

I'm aware of the need to have a way to exhaust air when running a roof top evaporative cooler.

The input air was at 27 C, the output air was about 4 C cooler, at 23 C. The physical temperature in the RV rose as the out door temperature peaked at 31 C. I did take humidity readings--but I failed to record them.

I'm comfortable up to 25 c (77 f). The recirculating air evaporative cooler I purchased was not able to maintain the RV at 25 C, even though the makers rating was for 500 square feet when my RV is 241 square feet.

I don't understand how any kind of evaporative cooler can function to lower temperature in a closed environment regardless of where it is located. The cooling process adds moisture to the air raising the interior humidity and if it is just recirculating it keeps adding more humidity to the air reducing the cooling. To me it seems somewhat similar to operating a window A/C unit totally inside your closed RV with the cooled evaporator air and heated condenser air both being blown into your RV. Except in this case you would dehumidfy the air but not see any net cooling because the heat you absorbed in the A/C evaporator would be pumped right back into the RV via the condenser.