The power card contains two jumpers located below the tamper switch:
Jumper Setting. Cover both pins to Disable, remove jumper (store on 1 pin) to Enable.
The D341/D342 duct detector will not reset when using D344-RT Remote Test Kit. Turning the key to Test puts the detector in the alarm condition but turning to Reset does not return the detector to normal condition.
The Reset Jumper on the power card inside the D341/D342 has not been removed to enable the Remote Keyswitch Reset function. Remove the jumper below the tamper switch, on the right side.