Does the U-Bell DB1 have a battery connection?
The U-Bell DB1 is a wired only connection that uses 16 VAC to 24 VAC. Connect to your existing wired house chime without replacing with a new one.
Please connect a resistor (included in the box content) to the doorbell if no electrical chime or mechanical chime is connected. See your QSG for more information on using the resistor.