Experimental Validation of Design Cooling Load Procedures: The Heat Balance Method

The RTSM (Spitler et al. 1997) is a simplified, heat balance-based design cooling load method intended for spreadsheet applications. The RTSM is similar in concept to the TFM in that both methods are based on the principle of superposition. This means that these methods do not solve the system of heat balance equations simultaneously but calculate the individual heat gains independently of one another. The overall thermal response of the building element at a given time is equal to the sum of the responses caused by several input heat gain/temperature excitations during previous times. Although less accurate than the HBM, the RTSM has the advantage of allowing the user to directly compare the magni-Building thermal load calculations underpin the design of all indoor environmental systems. The accuracy of the thermal load calculation procedure is, therefore, of concern to heating, ventilating, and air-conditioning (HVAC) engineers, who design HVAC systems and/or perform building energy analy-