Generalized Performance Maps For Single And Dual Speed Residential Heat Pumps

This paper presents generic equipment models that capture the performance of families of similar heat pumps equipment and that can be used in building simulation programs. Mapping has been carried out for families of single and dual compressor speed ducted split systems and the correlations are being implemented as components for building simulation. The units mapped ranged in nominal capacity from 1 to 5 tons (3.5 17.6 kW) and 2 tons to 5 tons (7.0-17.6 kW) for the single and dual speed units, respectively. Equipment models for building simulation were generated based on the ASHRAE secondary toolkit direct expansion model. Single sets of correction factor equations were found for each family in heating mode and cooling mode by first aggregating normalized performance data of all the units in each family and then mapping the normalized performance characteristics using the ASHRAE toolkit model (Brandemuehl, 1993). The dual speed unit model was split into two parts; one set of coefficients for low speed and another for high compressor speed. These models are based on modern equipment currently on the market and provide a useful update to the currently available standard direct expansion air conditioner models in building simulation programs. The generalized models generated in this study were compared to established performance models based on the ASHRAE toolkit model for cooling and the DOE 2.1 RESYS routine for heating mode operation.