scope:

The recent ASHRAE project, "Updating the ASHRAEI ACCA Residential Heating and Cooling Load Calculation Procedures and Data" (RP-I 199), developed two new residential loads calculation procedures: residential heat balance (RHB), a detailed heat balance method that requires computer implementation, and residential load factor (RLF), a simplified d procedure that is hand tractable and suitable for spreadsheet implementation. This paper describes RLF and its development. The form of RLF resembles prior methods. However; the sensible cooling load procedure was derived using linear regression to j n d relationships between design conditions, building characteristics, and peak cooling load predicted by RHB. This eliminated the need for semi-empirical adjustments, such as averaging, that have been used in the development of other methods. Results comparing RLF to RHB are presented. The RLF heating load calculation is also described; it uses the traditional UAΔT formulation except for improvements to procedures for infiltration leakage rate and ground (slab and basement) losses.