Multi-criteria performance evaluation of an HVAC control system

Abstract

A precise evaluation of HVAC (Heating Ventilation and Air Conditioning) control systems in buildings provides the opportunity to ameliorate the component processes involved in maintaining a high standard of Indoor Environmental Quality (IEQ). As such testing is not done regularly, it is not known whether the control system is working correctly. Assessing controller performance allows engineers to streamline the cooling and ventilation processes. An energy-efficient HVAC system is consequently developed the long-term. In this research, it was hypothesised that the HVAC controller does not consistently achieve all the set parameters within a reasonable time frame. The Field Environmental Chamber (FEC) situated in the School of Design and Environment (SDE) facilitates the assessment of the Honeywell Building Automation System (BAS) under laboratory conditions. The results demonstrate that although the HVAC controller successfully achieved and maintained the set parameters, the time taken for separate tests was not consistent. It also had difficulties achieving multiple set parameters of temperature and relative humidity (RH) during trials. Whilst a more rigorous study is needed, the procedure is often excessively time-consuming and the interface software lacks the ability to perform self-diagnostics or automated testing of multiple set parameters. Nevertheless, regular testing would allow feedback and modifications to be effected more rapidly and eventually lead to a more robust system. From FEC tests, it was apparent that there is still room for further enhancement of the HVAC control processes on a micro level as well as implementation of more sophisticated control strategies on a macro level.