The invention relates to the technical field of the lithium bromide absorption-type machine unit control. A load adjusting method relates to a single/double effect lithium bromide absorption-type refrigerating machine; and the machine unit is added with a refrigerant adjusting system which adjusts the overflow quantity of the refrigerant from an evaporator to an absorber, thus adjusting the load of the machine unit. The method has simple structure, is additionally provided with a bypass pipeline and an overflow valve in the traditional machine unit, controls in real time by a control loop, conducts the adjustment of the overflow quantity of the refrigerant according to the size of the load, adjusts the load by adjusting the overflow quantity of the refrigerant, and does not adjust the input heat by a control valve, therefore, when being loaded partially, the machine unit not only can stably run to guarantee the refrigerating requirements of a user, but also can consume the waste heat generated by a technique completely by the machine unit, and has no influence on the operation of the technique of the user. Simultaneously, the control loop formed by liquid level detection and the controller protects a refrigerant pump and prevents the cavitation erosion phenomenon occurred on the refrigerant pump and has wide application scope.