I have an 80 sqft bathroom and recently installed a 110 cfm Panasonic bath fan. If the furnace or AC is on, everything is fine. If not, moisture accumulates all over the ceiling, walls, the light, mirror, window, etc. There are now water marks on the walls where the moisture has run down the walls.
The bathtub/shower is one wall with the vanity & toilet across from it. The fan is between the vanity & toilet. I fan is on a timer and runs for 30 minutes after we turn the light off, so likely runs for an hour after shower is complete.
Is this normal? I've used bathrooms in the past while never running an exhaust fan and never seen moisture accumulate like this.