Aspects of liquid operational systems are described. According to one aspect, a system to automatically fill a liquid operational component is described. According to another aspect, a self-diagnostic system is described. According to yet another aspect, a flow conditioning arrangement is described. A control system for a heat-transfer system includes a plurality of sensors. Each sensor is configured to observe an operational parameter indicative of a thermodynamic quantity and to emit a signal containing information corresponding to the observed operational parameter. Control logic includes a processing unit and instructions stored on a memory that, when executed by the processing unit, cause the control logic to determine a first thermodynamic quantity associated with each sensor from information contained in a signal from the respective sensor; determine a second thermodynamic quantity associated with each sensor from information contained in a signal received from at least one other sensor in the plurality of sensors; compare the first thermodynamic quantity with the second thermodynamic quantity; and responsive to the comparison of the first thermodynamic quantity with the second thermodynamic quantity, output a control signal.