In order to meet the requirement of the heating thermal comfort and indoor air quality

the energy flow mathematical model for the central air conditioning system with air-source heat pump water chiller and fuel combustion boiler were established in sequence to finally determine global energy flow through analyzing the comparative energy flows of the consecutive loops which begin from extraction energy from the environment and provide it to the conditioning space. As a case study

the two energy flow diagrams of heating modes with different heat sources at a hotel in Guangzhou were drawn respectively

which can visualize each energy flow

energy balances

energy losses and their main differences. Recognizing the main energy flow of the two heat sources can provide useful messages for selection and energy saving of heating mode of conditioning system.