Burnett Holdings

The building consists of retail tenancies on the ground floor and office fit-outs on the first floor, so a solution which could cater to all tenants’ needs was required.

The Challenge

Initial construction was a base-build mechanical services arrangement throughout the building. With multiple tenancies, a variety of needs and a relatively small foot print, a VRF solution was the natural choice.

As office tenants were signed up, there was a need to have a mixture of smaller offices as well as larger open spaces. This presented issues around having a solution that suited the tenants’ needs as well as being compliant with AS/NZS-5149.1.2016 standard (which superseded AS/NZS-1677.2:2008) in regards to the maximum refrigerant concentration and the safety of the occupants during a potential leak. The inclusion of this standard was considered as part of the Safety By Design for the project.

The Mitsubishi Electric Solution

A combination of traditional City Multi VRF and City Multi Hybrid VRF (HVRF) was adopted to provide a solution that suited all the projects requirements. Traditional VRF was used in larger areas where refrigerant concentration was not a concern and HVRF was used in the smaller areas where VRF would be non-compliant with AS-NZS5149.

The small additional cost of Mitsubishi Electric’s City Multi HVRF was less than any refrigerant monitoring that would have been required to make a traditional VRF solution compliant. The solutions still retained the ability of all systems to simultaneously heat and cool, and allowed the requirements of each space to be satisfied.

The modular system architecture of City Multi VRF and HVRF allowed for a reduced outdoor plant footprint, extended pipe runs and the added efficiency of heat recovery, while still retaining separate systems for each tenant to enable simple power billing and tailoring to their individual needs.

Equipment Breakdown