A heat pump dispenser includes a housing having a handle portion and a barrel portion. A feeder section is coupled to the handle portion. The feeder section includes a feeder mechanism and a dispensing trigger assembly operably coupled to the feeder mechanism. The feeder mechanism includes a gear assembly having a drive gear operably engaged to a plunger housed in the barrel portion. The trigger assembly includes a trigger having a ratchet portion. The ratchet portion selectively engages and rotates the drive gear to move the plunger toward a dispensing opening provided in the barrel portion and into engagement with an adhesive/filler stick. The feeder mechanism is selectively actuated by the dispensing trigger assembly to advance the adhesive/filler stick into a heater section of the barrel portion.
