A solder handling assembly comprises a heating portion, a casing, a variable resistor, a connecting member coupled to the variable resistor, and an elastic-resilient member movable from a first state to a second state. The connecting member is rotatable relative to the casing and is configured to adjust a resistor value of the variable resistor when the connecting member is rotated relative to casing. When the elastic-resilient member is in the first state, the connecting member is prevented from rotating relative to the casing. When the elastic-resilient member is in the second state, the connecting member can be rotated relative to the casing.