AbstractMostly agricultural product have high moisture content that can attract microorganism to grow on the product and occurs metabolic activity which can decreased the quality of the agricultural product. In order to prevent it, preservation the product by drying process is needed. On this research, drying heat pumps were built and tested at the Laboratory of Sustainable Energy Research Center (SERC), Faculty of Engineering, Universitas Sumatera Utara. Heat Pump drying chamber has length, width and height of 100 cm x 80 cm x75 cm. By having one chilli rack with the length and width of the rack was 40 cm x 40 cm, with a volume of drying space. The research was tested to reduce the red chilli water content from 80% into 5% with heat pump dryer takes 30 hours 50 minutes long. The inlet area of the drying room was 94 cm x 10 cm for the inlet of 6 cm x 6 cm. The heat pump working fluid itself uses refrigerants, here are the types of refrigerants such as R22, R410A, R11, R12, R32, and so on. R32 is a new refrigerant that more environmentally friendly and more efficient at conveying heat than others refrigerants. This heat pump system for drying chilli can be used for various agricultural products and can be applied for industrial products.