To improve the efficiency of domestic hot water (DHW) systems in a heritage-listed commercial building, a project at 180 Queen Street, Brisbane, was undertaken. Managed by Cornerstone Property Services, the building required a modern, sustainable solution to replace its aging electric DHW tanks while preserving its heritage integrity.
- Location: Brisbane (QLD)
- Industry: Commercial
Challenge:
The heritage-listed building at 180 Queen Street, Brisbane, managed by Cornerstone Property Services, needed an upgrade of its domestic hot water (DHW) system. The existing electric DHW tanks, installed on six floors (excluding level M, which had no DHW/DWWS requirements), were inefficient and required modernisation. The goal was to introduce a more sustainable, reliable, and efficient solution while adhering to Australian standards and preserving the building’s heritage integrity.
Our Checks:
Project Scope:
Oventrop, in collaboration with Masterflow Solutions, was engaged by project design consultant Floth and HVAC refit contractor Dewpoint Group to replace the existing electric DHW tanks with advanced Regudis Heat Interface Units (HIUs) on six floors..
Equipment Used:
The Regudis W-HTE single-plate HIUs, capable of delivering up to 21 L/min of 43°C domestic warm water supply (DWWS) via a plate heat exchanger, were selected. These units operate from the base building’s air-cooled Multifunction Heat Recovery Chillers, utilising a continuous 48°C primary hot water supply for optimal performance.
Compliance:
The installation complied with Australian Standards AS3500.4 clause 1.9.3, the Plumbing Code of Australia, and local government guidelines for warm water systems. The Regudis W-HTE as a DWWS appliance-based solution eliminates the need for tempering valves or expensive thermostatic mixing valves, ensuring optimal system hygiene, reduced maintenance costs, and, most importantly, reliable operational safety.
Diagnosing the issue:
Existing System:
The electric DHW tanks on each floor were not energy-efficient and could not meet modern performance or sustainability requirements. The inefficiencies led to high energy consumption, inadequate water temperature control, and hygiene concerns due to outdated infrastructure.
Challenges:
The main issue was integrating a new DHW system that could utilise the building’s existing infrastructure while ensuring reliable and hygienic delivery of warm water. The limited space within a heritage-listed building also posed installation challenges.
Solution:
Regudis Heat Interface Units:
The Regudis W-HTE HIUs, with advanced electronic flow rate and temperature control, provided an ideal solution. Their compact, water-to-water design allowed for hydraulic separation between the DWWS and the primary heating hot water supply, ensuring potable water was delivered hygienically at optimal temperatures.
The asymmetrical HEX plate arrangement minimised pressure loss and enabled lower primary water temperatures without sacrificing performance. This upgrade significantly improved energy efficiency, reduced the building’s carbon footprint, and ensured compliance with DWWS hygiene standards.
Environmental and Community Impact:
This project exemplifies the “blue to green” concept by providing a more sustainable solution that benefits both the environment and the building’s occupants. The refit reduced energy consumption and improved operational efficiency, contributing to long-term savings and environmental sustainability.