Hey everyone! Scott Farrell here. Currently I have a small 8x8 greenhouse which I've had for about two years.

I have a fairly large swamp cooler for the summer months and have traditionally always kept the swamp cooler fan on "HIGH" speed. Until a few months ago....

It was in May that we had a record 105 day. I was at a special event when my roommate called to say that the temperature alarm had gone off and the greenhouse was 95 degrees... he said the swamp cooler wasn't working. I had hooked up a thermostat that had worked for about a year with not problems.

I thought the pump had fried and luckily I had a replacement. After replacing it and seeing that that wasn't the problem I finally after a couple of hours figured out it was the thermostat (even tho it appeared to be working fine).

I found out that the thermostat had gone bad.. so quickly thinking, I unplugged the pump from the thermostat and "hot wired" it directly to get water flowing. I then lowed the temperature on my exhaust fan (really a non-necessity with the swamp cooler) and found out that my greenhouse temp dropped LOWER even on this 105 day then it did with the swamp cooler running on HIGH. What appeared to be happening was less air movement.

Thinking this through, I switched the swamp cooler to LOW FAN rather than HIGH fan, and sure enough, it seems to keep my greenhouse about 8-10 degrees cooler on LOW than on HIGH.

Has anyone else experienced this? I'm guessing the slower air movement is picking up more water over the pads or has more time to circulate before being blown out the exhaust vent(s).

I've always loved water walls or wet walls and I'm planning on installing one of those in my 19x26 greenhouse I'm currently building.

Just thought I'd throw my question out to see if anyone can explain my experience! ...and to help anyone who MIGHT be in the same predicament of trying to keep their greenhouse cool in the hot Sacramento summer weather. I guess MORE isn't always better?

Scott