I hope there is an easy fix - I purchased a new Carrier Weathermaker 9200 about 7-years ago. Not getting much humidity so I went to change the water pad in the Aprilaire 700 humidifier. The pad is scale free, the fan is spotless - both look like they have never been used - I have seen the humidifiers after a couple of years and know they get very thick buildup. I tried to do the test mode on the humidifier with the furnace fan running and nothing happened. I checked the wireing and nothing is obvious. I don't think this thing has run for years. any advice?
turn the humidistat to the test mode, turn temperature up on furnace at thermostat......make sure the water is on to the humidifier. wait a few minutes and you should have water flow and the fan should be running,if not you will need a volt meter to start trouble shooting.