Paper Conference

Proceedings of eSim 2018: 10th Conference of IBPSA-Canada


Variable capacity mini-split air source heat pump model for TRNSYS

Guillaume St-Onge, Michaël Kummert, Martin Kegel

Abstract: Air to air heat pumps have long been used in the Canadian residential sector as an energy efficient space heating solution, despite their limitations in cold weather. Recent technological advancements have seen the use of inverter driven compressors, which not only has the capability of increasing the heating capacity while maintaining above 100% efficiencies at low ambient temperatures, but also better efficiently meeting comfort conditions at warmer temperatures. Although improved efficiencies are advertised, there is a lack of simulation models available for building designers to estimate the energy saving potential. While some studies have qualitatively evaluated compressor speed, it proved difficult to find one that explicitly measured the frequency to clearly establish its impact on variable capacity air source heat pump (VCASHP) performance. Detailed performance testing was therefore conducted on a VCASHP varying the ambient temperatures and load imposed on the heat pump while measuring heat flows and compressor speed. This allowed to build a detailed performance map of this system, and develop an effective component model to dynamically estimate VCASHP performance in TRNSYS.
Keywords: Building simulation, Air source, Variable capacity, Cold climate, Ductless mini split heat pump, Defrost cycle
Pages: 40 - 49