My whole house powered humidifier stopped working last year. Finally decide d to do some troubleshooting and noticed that the 24 volt humidifier circui t is never getting triggered. Using a voltmeter on the board I never get an ything higher than 11 volts. The Transformer is putting out 24 volts as is the thermostat. Is this a common problem? Is the solution of new control bo ard for the furnace? Anything else I should try?