I have two units, one upstairs and one downstairs. I recently had both capacitors replaced in my outside units now they are running great. My question is on my Robertshaw 9420 thermostats on the bottom it says cool with the fan symbol turning on the left and two fan symbols turning on the right of the word cold. My other thermostat indicates the same except there is only one fan turning on the right side of the world cold. Is there something I need to change or is it better left alone?