Melbourne Commercial Office Tower – ENERMAX SMARTcube Heat Pump system


A Melbourne CBD office tower of 17 levels requiring replacement of the water heating plant to service office amenities on all levels. The new system is to ensure reliable supply of hygienic hot water, deliver energy usage reduction, improved plant durability and free up plant room space.

Essential that the system replacement be conducted at lowest possible cost and with minimal disruption to hot water supply.

System Requirements:

Reliable, uninterrupted hot water delivery over 17 levels. Must be capable of delivering a consistent 1,650L per hour at 65°C. Energy efficiency to be superior to the original system, footprint no greater and ongoing maintenance requirements minimised.

Original System:

8-year-old gas boosted system comprising:

  • 3 x instantaneous gas burners (one of which had been decommissioned)
  • 3 x 1,000L stainless steel storage tanks

Plant was failing to meet delivery requirements and energy efficiency targets, with maintenance costs higher than desired.

ENERMAX System Solution:

  • 9 x ENERMAX SMARTcube unpressurised 500L tanks – SC500, comprising dual stainless-steel coils for hygienic hot water and high flow rate capability.
  • 3 x ENERMAX High Temp 32kW Commercial Heat Pumps, at 3.48 COP (Co-efficient of performance)

ENERMAX Heat Pump system is BMS compatible, so is integrated with the building’s monitoring system (BMS) to measure and monitor operation, energy consumption and efficiency.

The system can be linked in future to Solar PV panels as an additional energy source, to further reduce energy consumption and carbon footprint.

System Performance:

  • Energy Reduction – significantly reduced energy usage, as system thermal efficiency is improved from previous 80% (original system) to 348% through the heat pump’s superior COP.
  • Delivery – consistently delivering up to 1,650L per first hour at 65°C over all 17 levels.

  • Footprint – total footprint is less than the original system. Being 100% external installation, plant room space is not required.
  • Hygienic heated water supply – the unique ENERMAX SMARTcube design passes water being heated for consumption through dedicated 316 Stainless Steel coils, separated from heat exchange water in the tank.
  • Installation changeover/retrofit disruption – the modular system was built in the TES Commercial hot water plant, then disassembled and brought on site without the need for external cranes or lifts. It was then reassembled in-situ with minimal disruption to building DHW supply.
  • Durability – the primary loop within the ENERMAX system is unpressurised, reducing wear for improved durability and less ongoing maintenance.


This ENERMAX solution provides significantly improved energy efficiency without the need for additional boosting and the ability to monitor performance and efficiency through the BMS.

Heated water is reliably and consistently delivered over 17 levels from a single system. Externally installed with minimal disruption to water supply when retrofitted in position, space saving is maximised. The unique design delivers improved long-term durability and lower maintenance costs.