Paper No 777 – Cold Climate Field Demonstration of Variable Refrigerant Flow (VRF) Heat Pump and Variable-Air-Volume (VAV) System – 14th IEA Heat Pump Conference, Chicago, USA
Heat pump variable refrigerant flow (VRF) systems are increasingly used in U.S. small commercial buildings to provide cost-effective efficient heating and cooling for multi-zone applications. The complexity and customized design of VRF systems for specific buildings make it difficult to predict energy savings relative to other HVAC systems. Due to limited VRF field data, especially in colder climates, energy savings are often based on energy modeling or laboratory data obtained under controlled conditions. A field demonstration at Naval Station Great Lakes (NSGL) in Illinois offered a unique opportunity to directly compare measured performance data for a VRF system to the baseline variable-air-volume (VAV) system for the same building. The objective of this demonstration was to evaluate the performance of two VRF systems: an electric cold climate heat pump and a natural gas engine-driven heat pump in a side-by-side installation for a small office building compared to the existing VAV system. This paper will focus on the benefits and limitations of the electric CCHP VRF system compared to the baseline VAV system for cold climate applications. The VRF system paired with a dedicated outdoor air system (DOAS) significantly reduced the facility peak electric demand, greenhouse gas emissions, and energy costs compared to a conventional VAV system.