By Eamonn Ryan with technical input from Deon Kotze, sales and technical manager: Mitsubishi Electric Air Conditioning Systems, and Riaan Marais, consulting engineer with SHC

Irene Hotel in Pretoria recently underwent a significant transformation, thanks to SHC Consulting’s modernisation of the hotel’s ageing air conditioning and hot water systems.

The new building housing VRF City Multi equipment.

The new building housing VRF City Multi equipment. All Images provided by Mitsubishi Air Conditioning Systems

Irene Hotel is well-known for its picturesque surroundings, including a working dairy farm, providing a unique atmosphere for guests. Riaan Marais, consulting engineer with SHC, shared insights into the project, which aims to enhance guest comfort while maintaining operational efficiency. “The hotel’s previous chiller system had served its purpose for over 25 years, but it was time for an upgrade. Being in the hospitality sector, it was important to keep the hotel operational during the renovation. Therefore, the project was executed in phases to minimise disruption. We planned the whole project primarily during the winter months, allowing us to switch rooms’ air conditioning on and off without shutting down the entire facility,” he explains.

Central to this upgrade is the integration of Mitsubishi air conditioning units and heat recovery systems, which were also utilised in a previous RACA-profiled project at University of the Free State. This consistency in suppliers ensures reliability and performance. Marais highlights that the new system is currently performing exceptionally well, providing an efficient hot water supply that capitalises on the energy generated by the air conditioning units. “We’re essentially getting hot water for free, as the system utilises energy from the air conditioning units while running in guest rooms,” he notes.

Hot water boosters 2x off feeding the uncladded water tanks. One tank consists of a 2 500ℓ each, also showing the pipe work

Hot water boosters 2x off feeding the uncladded water tanks. One tank consists of a 2 500ℓ each, also showing the pipe work

Mitsubishi transforms HVAC systems at Irene Hotel

Marco Ferdinandi, marketing director at Mitsubishi Air Conditioning Systems, says: “The project involved the installation of Mitsubishi Electric’s Variable Refrigerant Flow (VRF) systems, specifically the VRF City Multi series, renowned for its energy efficiency and advanced technology. With meticulous planning and execution, Mitsubishi Electric engineers replaced outdated equipment with state-of-the-art VRF systems, ensuring enhanced comfort and energy savings for Irene Hotel’s guests.”

He detailed the technical aspects of the project, highlighting the specific equipment utilised, including the VRF City Multi systems. “These systems offer efficiency and performance, making them an ideal choice for commercial applications such as hotels. One of the notable challenges faced during the project was the need to maintain hotel operations while installing the new HVAC systems.” However, careful planning and implementation strategies allowed the Mitsubishi Electric team to overcome these challenges without disrupting guest comfort or hotel functionality.

In addition to the HVAC upgrades, Mitsubishi Electric also addressed Irene Hotel’s hot water requirements. By leveraging the innovative heat recovery capabilities of its VRF systems, Mitsubishi enabled Irene Hotel to simultaneously provide cooling to guest rooms while generating hot water, thereby optimising energy utilisation and reducing operational costs.

The hot water copper piping layout for the hot water. The tanksfeed all the bedrooms per block

The hot water copper piping layout for the hot water. The tanks feed all the bedrooms per block

Reflecting on the project’s objectives, Ferdinandi emphasised the importance of energy efficiency and sustainability. By replacing outdated equipment with cutting-edge VRF systems, Irene Hotel not only improved guest comfort but also achieved significant energy savings and reduced environmental impact.

Moreover, he highlighted the versatility of their VRF systems, which can cater to diverse needs, including both HVAC and hot water supply. This holistic approach ensures comprehensive solutions tailored to meet the specific requirements of each customer, resulting in enhanced performance and operational efficiency.

Ferdinandi emphasised the significance of energy efficiency in the project. He explained that the new VRF systems deliver impressive performance, with a coefficient of performance (COP) of six or above. This means that for every one kilowatt of energy consumed, the system generates six kilowatts of total capacity, resulting in significant cost savings for the hotel.

Furthermore, the project addressed Irene Hotel’s hot water requirements by leveraging the heat recovery capabilities of Mitsubishi’s VRF systems. By simultaneously cooling guest rooms and generating hot water, the hotel achieved optimal energy utilisation and reduced operational costs.

In addition to the technical aspects, the project also highlighted the importance of sustainable practices in the hospitality industry. By investing in energy-efficient solutions, Irene Hotel not only improved guest comfort but also minimised its environmental footprint. Despite the project’s complexity, Mitsubishi executed it seamlessly, ensuring minimal disruption to hotel operations. The installation process, which spanned several months, involved careful planning and coordination to replace outdated equipment and integrate the new systems without inconveniencing guests.

Looking ahead, Irene Hotel is exploring additional measures to further reduce its reliance on conventional energy sources. While solar energy solutions were not included in the initial project, the hotel’s management is considering future initiatives to enhance its sustainability efforts.

Overall, the Irene Hotel project exemplifies the impact of energy-efficient upgrades in the hospitality sector. By partnering with Mitsubishi Electric, the hotel has not only improved its operational efficiency but also improved its sustainability within the industry.

Mitsubishi Electric’s City Multi VRF air conditioning systems are designed for medium to large buildings and can provide heating and cooling for multiple zones simultaneously. They offer a variety of features, including:

  • Variable refrigerant flow (VRF): Recycles refrigerant between an outdoor unit and indoor units to provide heating and cooling.
  • Hybrid VRF: Uses a water system between the Hydro Branch Controller (HBC) and indoor units to provide stable temperatures. This system can save up to 30% on energy costs compared to traditional heat pump systems.
  • BC Controller VRF: The system’s decision-maker, which enables simultaneous heating and cooling.
  • Flexible design: Can be installed in phases and adapted to changes in office layouts.
  • Light equipment: Easy to manoeuvre and install, and can reduce labour and material costs.
  • Internet connectivity: Allows for off-site monitoring and management.
  • Control options: Includes a colour touch panel with a backlit LCD that displays the operation status of connected units.
  • City Multi VRF systems can be connected to up to 50 indoor units, including ceiling cassettes, wall mounted, floor standing, and more.

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