The Department of Climate Change, Energy, the Environment and Water (DCCEEW) has published the complete results of its refrigeration and air conditioning bench-testing project. It clearly demonstrates that preventative maintenance minimises technology failure, reduces refrigerant leaks, and increases the energy efficiency of properly installed equipment.
The project is the next stage of a much larger project to quantify the benefits of better installation and regular equipment maintenance practices. The first two stages identified the most common faults occurring in HVAC&R equipment and their frequency. This work was conducted by the Expert Group for the Department and was based on international studies. Next was an extensive Australian maintenance report on air conditioning faults by Grosvenor Engineering Group in collaboration with Refrigerants Australia and the Expert Group.
In the bench-testing phase, SuperCool Asia and the CSIRO tested four different refrigeration and air conditioning equipment for the common faults. Cresstec, with nine years’ experience of fault analysis and tracking, also provided bench test results undertaken independently to the project on an air conditioning unit at different Australian temperature zones, against similar common faults. Refrigerants Australia and the Air Conditioning and Refrigeration Equipment Manufacturers Association (AREMA) provided technical support to the Department for this phase.
Key findings
The bench-testing quantified the impact of common faults for the equipment tested.
- For refrigerated display cabinets, a 40 per cent blocked condenser reduced the system performance and increased its energy consumption by around 16 per cent.
- For walk-in cool rooms, contaminated refrigerant had the greatest negative impact on system performance, with the energy consumption increasing by almost 70 per cent over the reference run.
- For non-ducted split systems running at 70 per cent refrigerant charge, there was a drop in unit capacity by 17 per cent in the cooling cycle and 19 per cent in the heating cycle compared to the reference run.
- For ducted rooftop packages, at 100 per cent refrigerant charge with 51g of a non-condensable added (at T1 temperature zone), there was a drop in unit capacity of almost 18 per cent in the cooling cycle, and with 70 per cent refrigerant charge a drop in unit capacity of 55 per cent in the heating cycle, compared to the reference run.
According to the Department, the project has highlighted the importance of increasing the awareness of the benefits of routine maintenance with key messages targeted at equipment owners.
It also reinforced the benefits of working in collaboration with industry – businesses and peak bodies, academia and government to meet a shared outcome. According to the Department, this was demonstrated through the alignment and complementary results achieved across the earlier reports – Leaks, maintenance and emissions and Air Conditioning Faults – An Australian Analysis – and the six new bench test reports. The Department believes these will provide greater transparency to equipment owners on the most common faults in equipment, the frequency with which the faults occur, and the impact.
The full suite of bench-testing reports is available at the DCCEEW website.
Photo by Lukas: https://www.pexels.com/photo/person-holding-pen-pointing-at-graph-590020/
Good information for all systems management teams