Lasko model 1128 4.5 Gallon

We've had this for a couple of years, and it seems to work well. BUT....I'm not happy with the insides being enclosed to the point of not being able to "clean" it. Besides replacing the filter, which seems to need done often, I can't get to the fan which has dust on it. We have a gas fireplace, which we use often during the winter months, so this humidifier gets used a lot, but I don't feel it is putting out good clean humidity...worry about lime build-up on the inside of the unit.