PERFORMANCE VARIATION OF VERTICAL OPEN REFRIGERATED DISPLAY CASES IN-SITU OPERATION AND TESTING ACCORDING TO ISO AND ASHRAE STANDARDS

摘要

Refrigerated display cases are an equipment widely used in sales environments, such as stores and super markets. Most equipment are open type since they provide a good marketing appeal. This type of equipment is used to expose perishable foods or chilled drinks. Manufacturers seek during the design phase of the equipment to certify its suitability to the testing standards with the lowest energy consumption and ensuring food safety. With the aim to assist the development of new equipment that meet the test conditions established by testing standards and market needs, experimental tests were conducted comparing real operation conditions and test conditions following the testing standards ISO 23953/2005 and ASHRAE 72-2005. The experimental results show that test conditions required by standards are stricter than in-situ operation, providing higher conservation temperatures (56% increase) and energy consumption (17% increase).rnThe experimental study considers an open vertical refrigerated display case that demands high electrical energy consumption due to its characteristics. The tests performed in the laboratory using a climatic chamber determine approximately 17% higher thermal load values than those of in-situ operation with remote refrigeration system. This condition arises from the different airflow conditions that are found inside stores when comparing with the conditions and patterns imposed by standards for equipment testing. This difference has a negative impact in the commercial scope since equipment manufacturers relate lower thermal load values than those determined in tests of similar models according to standards.