Full Description

This paper describes the design, implementation, and early results obtained with an automatic electric heat pump data acquisition system (DAS) prepared for the American Gas Association and participating gas utilities by the authors and others over the last two years. A test program utilizing this DAS is currently collecting heating season performance data from 13 residential test sites located throughout the country. The objective of the test program is to collect realistic operating performance, durability, and cost data on contemporary residential air-to-air electric heat pump systems under actual residential heating and cooling load conditions.

Of particular interest is the design philosophy of the data acquisition system. It utilizes a personal computer configured as a datalogger and relies heavily on its custom data-logging computer program. The program not only collects data but monitors the entire system for faults and problems. Elements of the program are used to check the correctness of the data that are received. A data reduction program was also created to check the raw test data for errors, reduce them, and convert them into a format that can be handled by commercial spreadsheet and graphics programs.

Early results indicate that the DAS is operating as expected. Problems to date have been with secondary (backup) hardware and with incorrect manual data collection procedures, neither of which have resulted in substantial loss of data.

The DAS is currently being enhanced to also measure cooling loads through the incorporation of a method to measure the amount of water condensed in the cooling mode. This involved modifying the software and adding a modified tipping bucket water gauge to measure the condensate.

Units: I-P

Citation: Symposium, ASHRAE Transactions, 1986, vol. 92, pt. 2B, Portland, OR