No general boiling-water remedy should be used. The unit and connected pipework have model-specific temperature limits, and a blockage needs proper assessment.
What the observation means
A toilet macerator and a kitchen wastewater pump can have different capabilities. Pouring very hot water into an uncertain system can add damage or overflow risk.
A useful next step
Stop adding water when drainage is impaired. Identify the unit and describe the problem to the service team. Do not assume that more heat, more volume or a mixture of cleaners will safely clear an obstruction.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.