Adjustable Temp Electric Fans, Need help finding a sensor--page 2 Options

[computers4kids]

Currently I have dual electric fans, each on their own relay, that both come on around 180 degrees. I would like to reduce the fan noise from both fans coming on at once since my system stays cool easily and both fans tend to be overkill. I was thinking about having one fan come on around 180 degrees and the other come on if the temperature raises 10 degrees or so above. Fans 1 and 2 would also shut themselves off once each one dips 10 degrees below their set temps.

I see Jegs sells a kit that appears to do just this for around $150 that would control both fans. http://www.jegs.com/i/Derale/259/16789/10002/-1
Another possibility, would be to let Fan 1 continue to come on at 180 using the temp sender Renegade supplied, disconnecting the Fan 2. Jegs also sells the same adjustable unit for a single fan for $83. I would connect Fan 2 using the single controller for half the price. http://www.jegs.com/i/Derale/259/16779/10002/-1

What are your thoughts?

[Bartlett 914]

I would not use a sensor on the input. Only on the output. Use 2 sensors there with different temperature settings. I installed an oil cooler and mistakenly installed the sensor on the input side. This is almost always be hot enough to turn on the fan. The cooler or radiator will do some cooling without any fans used. You need to add additional air flow when the cooler itself cannot dissipate enough heat.