Thank you for contacting us.
No water could be an indication of an issue with the solenoid valve.
If you have an Automatic Control try putting it into test mode:
A. No click at the solenoid valve indicates an electrical problem. Contact the heating and air conditioning dealer to further check the electrical components of the Aprilaire Humidifier.
B. If the solenoid valve makes a click sound and there is no water draining from the unit, this would indicate the flow of water is being obstructed.
1. To determine if water flow is being obstructed, turn the dial of the humidifier control to the off position. The first location to check for an obstruction would be at the saddle valve located on the water line supplying water to the humidifier. When checking the saddle valve, make sure it is completely open. This can be done by turning the valve all the way to the left. If anything is clogged, it can be dislodged by turning the saddle valve all the way to the right and back to the left. Once this is done, turn the humidifier control dial above the click point and water should be coming out the drain line.
2. If water is still not coming out of the drain, check the orifice and in-line strainer to make sure they are not clogged. The orifice is located in the tube on the outlet side of the solenoid valve and the in-line strainer is located on the inlet side of the solenoid valve (see attached). The orifice may be cleared by inserting a needle through the small opening. The strainer may be cleaned by running it under warm water to dislodge deposits or replace it. After clearing and re-installing the orifice and strainer (be sure to double wrench all water connections), turn the humidifier control dial above the click point and water should be coming out the drain line.