I have an Aprilaire humidifier model 700 with the #56 humidistat with outdoor sensor. It was installed 7 years ago and has been running fine until now. I change the pad yearly. This season I noticed that the humidifier does not seem to be running. I keep the dial on the humidistat at 5. I turned it up to the test mode which is past 7 and it runs. But when I turn it back down to lower than 7 it stops. I can feel it is dry in the house so I know that there is not enough humidity and thus the humidifier should be running. There are 6 wires to the humidistat (but I did not touch any wiring). Nothing was altered, just a new pad replaced, but it was not running this season before pad replacement - but was running last season. I'm in the Chicago area. Thanks for any help!!!! James

Humidifiers - Aprilaire - 700 Humidifier