So the manufacturer for this sounder stopped including the built in pull down resistor. The sounder/siren circuit on the Vista series main board is a open collector. So the transistor is normally open when not energized but like every digital output it needs a pull down/pull up resistor. The simple fix is to use the “bell supervisor” resistor and bridge it to lugs 3 and 4 on the vista panel board.
If you don’t have the bell supervisor resistor a zone EOL resistor works as well and a zone double 3K resistor will work as well. The whole point of the resistor is to pull the open collector to ground.
You also do not cut the red jumper for the bell supervision.
