khansen30 is correct. When the recycle button is "On", the A/C compressor will be running even though the snowflake/A/C button may not be lit up. It's in the manual.khansen30 said:If the recycle button is on, so is the A/C. Some say it is so the air stays dry so that the windows don't fog. If just the A/C light is lit, you are getting outside air with the A/C on. Note: if you have the vents blowing air only on the floor, you cannot turn on the recycle. You have to have then vents only on the upper or upper and floor on. Sorry, only smelly air during cold months.