Why SMMS-7 VRF is Right for Medium-Sized Buildings
A Cooling Solution That Fits Mid-Sized Needs
There is a significantly higher proportion of medium-sized commercial buildings compared with large buildings in Southeast Asia. The Building and Construction Authority of Singapore reported that among commercial buildings submitted for benchmarking in 2017, office, retail and mixed developments with gross floor area under 15,000m² exceeded office, retail and mixed developments with gross floor area of 15,000m² or more.
Medium-sized buildings cater to a vast range of different use cases, and their air-conditioning usage patterns vary accordingly. Offices, retail outlets, and educational institutions need to maintain comfort levels for occupants throughout the work day, before shutting down for the night. Quick-service restaurants and full-service restaurants see their occupancy rise and fall according to mealtimes. Hotels see higher occupancy of their common areas during the day. These medium-sized buildings will have variable load capacities to account for their different cooling needs. Both hotels and apartment buildings will often see higher air conditioning use in bedrooms throughout the night.
In Singapore, the energy use intensity (EUI) of small commercial buildings was recorded as exceeding that of large commercial buildings, although on average EUI has decreased by 14% from 2008 to 2017.
On top of cost considerations and energy efficiency requirements, building operators of mid-sized buildings will also need to consider the cooling capabilities suited for variable occupancy loads, footprint of cooling systems and ease of management of the building’s HVAC system.
With this in mind, the Toshiba SMMS-7 VRF system was developed to meet the needs of medium-sized buildings, with cooling capacity that can range from 20RT to as much as 500RT, while at the same time offering cost and energy savings through its energy-efficient design.
VRF: An All-in-One Solution
The variable refrigerant flow (VRF) system differs from the water systems (air-cooled chiller or water-cooled chiller) typically used in large buildings, mainly because of the greater ease of integration, optimisation and control of the VRF solution.
The VRF solution includes built-in control capability without the need for auxiliary equipment. Customers can choose to have advanced controls such as a building management system with energy monitoring. Air conditioning controls can be given to the building occupants or handled centrally by a facility team. Simple controls can be provided for functions such as the on/off controls, fan speed and temperature adjustment. The new intuitive UI design of the latest Toshiba Touch Screen Controller allows for easy and smart management of all air conditioners (up to 128 indoor units) in a business setting with minimal training and experience.
Water systems often utilise auxiliary equipment such as pumps, cooling towers and controls supplied by different vendors. It will still be necessary to work with different suppliers to integrate these components into the overall system. Beyond the integration process, a water system also necessitates a more complicated management process due to the wide variety of equipment and the multiple vendors that need to be involved. This is in comparison with the Toshiba SMMS-7 VRF, a single solution that simplifies integration and management, almost like a plug-and-play system.
For medium-sized buildings, the VRF solution also compares favourably with the simple split system (simple DX system). A single split system, in which an outdoor unit is connected to the indoor unit by a copper pipe, is individually controlled and is more suitable for home or small building use. Building operators in medium-sized buildings benefit from central control capability with the VRF solution, which a single split system lacks.
SMMS-7 can support design configurations from 8HP to 60HP in a combined module, and more combined modules can be installed according to cooling loads required. It is equally important to consider an air conditioning system’s part load performance, which is below the design load but which occurs most frequently. The system has best-in-class efficiency of up to 4.82 at full load and 7.27 at 50% load, making it an economical solution for mid-sized buildings. SMMS-7 utilises a twin rotary compressor which enjoys superior efficiency across a wide operational range. This ensures that the refrigerant is compressed only at the required pressure, which is varied according to the cooling load during the compression cycle. This in turn provides greater energy savings in the part load situations (such as 50% load) that occur most commonly, unlike other compression technologies that need to bring refrigerant up to full compression before cycling down.
SMMS-7 has the advantage of modular configuration, so that each system can deliver 60HP of cooling capacity. SMMS-7 has a diversity factor of up to 200%, so that any combination of indoor units can be connected to fewer outdoor units to satisfy various cooling loads and scenarios in medium-sized buildings. Hotels, for instance, can be fitted with up to twice as much indoor unit capacity as outdoor unit capacity, so that they can cool both common rooms during the day and guest rooms at night.
Minimum Footprint for Medium Buildings
Medium-sized building operators and owners need to maximise usable floor and rooftop area, and SMMS-7 VRF has a distinct edge in this regard. The improved accumulator design does not require a U-Pipe and allows for a more compact compressor footprint, even with its larger capacity. With its smaller footprint, building operators and owners have the flexibility to install the SMMS-7 outdoor unit on a rooftop or building ledge while freeing up space for other building facilities. Installation does not require complicated equipment, and in most cases, a service elevator is sufficient to transport the outdoor unit.
Some medium-sized buildings require a plant room with a dedicated engineer and specialised controls for its air conditioning equipment. No such plant room is required for the SMMS-7 VRF system. This frees up valuable real estate for sky gardens, restaurants, car parks or any other usable square footage[AW1] , providing opportunities for building owners to monetize these areas that may not have been available before. SMMS-7 also has built-in controls to help with zoning and set point management during normal operation, so that no dedicated engineer is needed. All of this further reduces the footprint and staffing overhead required for the system.
Medium-Sized Building Needs Guaranteed
With SMMS-7 VRF’s space saving configuration that can reduce up to 24% footprint, and a design flexibility that can diversify installation of outdoor units, owners of medium-sized buildings are poised to gain cost savings with this next-gen cooling system. From offices to restaurants and small boutique hotels, Toshiba SMMS-VRF guarantees reliable cooling performance for varying usage needs, sans the high installation, maintenance, and servicing costs.Back to Blog