ECN Forum Forums General Topics of the Trade General Discussion Area cental a/c

The typical central A/C will cycle every 30-40 minutes Do you think it's more economical to leave the Fan run constanty in manual or in auto so it cycles with the compressor?What do you do?

Leave it running, or at least in low, and jump to high when the A-coils are cold.

If you're talking about pure efficiency as energy (in BTU's) removed from the conditioned space vs. energy spent on running the ac, then having the fan off is slightly more efficient.

But if you're comparing dollars spent on electricity for the same comfort, leave the fan running.

With the fan off, air tends to stratify, with the cold air down by your feet and the air up at your torso and head being warmer.

But if the fan runs and the air keeps circulating, this doesn't happen. So you can be comfortable at 76º instead of 72º and that saves energy.