Evaporative Water Coolers - Single Pad or Double Pad?

I bought my house 16 years ago. High desert area, low humity, high temps. It was my first experience with an evap cooler, so I asked the Journeyman HVAC guy at work to come check it out and give me some instructions advice on how to use it and service it.

He advised me at the time that I would get better cooling if I used double pads. He said that the double pads would provide more area for water absorption and hence air cooling. Also, one pad should be tucked under the area at the top where the water drain holes are, and the other pad should be a lilttle higher and outside the water drain hole area to catch any water that might splash over the sides to make the best use of the water.

I have been doing that every year when I service and replace my pads. I use grass pads.

The HVAC has since retired. I was talking to my repair guy today about my evap cooler because I want him to check out the squirrel cage because it is very loud and vibrating. He suspects it might be a bearing and is coming out tomorrow to check it out. He says he has the tools to replace the bearing, but I digress.

I mentioned to him that I double pad, and why. He said that the humidity in our desert area has increased over the past 16 years, and that I should not be double padding because it reduces the air flow through the pads and that I am not getting the maximum cooling because of that.

So now I am confused. I have a fairly good understanding of how evap coolers and A/C units work and air movement for cooling, etc. But single pad or double pad ?? A monkey wrench has just been thrown into my evap cooler thought process, so I am asking the experts.

It has been my experience over the past 16 years that my double pad method has worked well - but then I have never single padded, so I don't know. My evap unit is a wall unit and has two speeds, high and low - no t-stat. I start out on high to get things cooled down and then generally find that keeping it on low, with the appropriate door/window openings for drawing the air to the other side of the house, is sufficient and comfortable. This is during low humity times, which is most of the warm/hot season (80-115 degrees).

So, to single pad or double pad, that is the question. If I have not provided sufficient information, please let me know.

Thanks,

Judy

Doubling your pads is fine, I've done it for years. Your airflow is not cut down that much, and with the humidity up, you could use the extra little bit of cooling.

Something to consider, you might want to think about switching over to a single inlet unit that comes with a 12" celdek pad, they cool much better and the maintenance on them is less. The pad in that unit is generally good for 4 or 5 years provided you use a bleedoff or purge dump to eliminate scale buildup.

Thanks, Sammy. I think I will probably continue to double pad. It has worked for me for 16 years......

Eventually I will need to replace my evap cooler and I will look into those new kinds of coolers that you refer to. I think my boss installed one at his house a few years ago.

Judy

Just for a point of interest, Adobe air who built the mastercool single inlet cooler, is now out of business. Champion cooler corp bought the mastercool name and is labeling it on their single inlet model.:)

Sammy,

that is much more than just a point of interest! It is directing me to the proper source for that specific cooler!

Thanks,

judy