Wait5000 humidifier problem

Hey guys. I have Wait 5000 installed on my furnace for the last 10 years . It was working till last week. Problem - no led light and water is not flowing on furnace heating cycle. I checked all system and what I got - 24 v to humidistat and 24 v to cycle board, but no power from cycle board to solenoid. I bypass from humidistat to solenoid and solenoid is working when I turned humidistat up and water is flowing. I called Air King and they sent to me new cycle panel to replace. I did and had the same result- no out power to solenoid and no led light. Then I got one more new cycle board and no luck. Its very hard to believe that all three new boards are not working. Maybe someone have an ideas what could be wrong. Thank you