aprilaire humidifier

my house in NJ has an older model of Aprilaire whole-house humdifier 550 with manual controller, it did not work for many year until I have plumber remove saddle valve and re-route water tube that goes to humidifier. However, I found out the water keeps flow into humidifier even hot-air furnace is not running, water continues to drain to small pump attached to furnace, then it pumps water out of house every few minutes.

Is this correct, water continue to flow even the blower of furnace is not running?? do I need to fix/replace some parts?? the controller seems to work because water can be stopped by adjusting controller. Thank you.

It should be wired so that it only can come on when the blower (fan) motor is on. Your furnace may have the ability to do this internally, or, you can purchase a sensing switch that will detect that the blower is on and enable the humifier. If you check the AprilAire website, they list this.

problem solved

It turns out that the transformer was hard-wired in junction box of furnace by contractor 'Air Group' (Aprilaire dealer in my area) in the first place, no relay sensor, of cause water will constantly flow as long as humidifier control is on.
After researching and studying on web, I found my Trane furnace has HUM connection, re-wire transform to it, solved the problem
Can we trust any contractors in these days??