Toshiba Air Conditioners - VRF-systems - SMMSi Outdoor Units 

Toshiba SMMSi = 3 compressors + maxumum efficiency

Toshiba SMMSI 3 compressorsToshiba SMMSi is the first in the air conditioning industry to control all the 3 compressors with a dedicated inverter board that taps the compressor’s full potential to provide smoother operation.

The 2-pipe VRF SMMSi operates with R-410A refrigerant and incorporates the latest inverter technology in all outdoor unit models. In addition, the SMMS incorporates twin-inverter compressors in every outdoor unit. The capacities range from 14 to 135 kW in cooling mode and 16 to 150 kW in heating mode with the capability to serve up to 48 indoor units. 13 different indoor unit models available in 81 sizes ensure system flexibility.

    Industry-leading energy savings

    Adopting the highly efficient new DC twin-rotary compressors and advanced vector-controlledinverters realizes a COP of 6.38 (under 50% partial load). Greater operating performance is now possible when operating under a constant load.
      Toshiba SMMSi system
    • Part load operation
      A VRF system can achieve energy efficient operation especially in a separated room layout as shown. Not all of the indoor units operate at the same time so the system is almost always operating with a partial indoor unit load. Toshiba SMMS has a world's highest COP at a part load - up to 6.38
    • Vector-controlled inverter
      The inverter boosts efficiency by controlling R410A and a twin-rotary DC compressor. Smooth sine current curve realizes higher efficiency and less noise.
    • Outdoor heat-transfer
      Compact heat-transfer tube with intakes on four sides. Tubes with improved heat-transfer coefficient of the inner surface.

    New intelligent VRF control

    Toshiba’s newly developed intelligent VRF control ensures that the right amount of refrigerant to satisfy the demands of each room, regardless of the type of indoor unit used and the length of the pipes.


    Infinity variable control adjusts compressor rotation speed in near-seamless 0.1 Hz steps. Responding precisely to the capacity needs of the moment, this fine control minimizes energy loss when changing frequencies, and also creates a comfortable environment subject to minimal temperature variations.


    Layout flexibility with few design limitations

    System layouts can use a maximum equivalent distance of up to 235 meters. This makes it much easier to design for floors with many small rooms, or for tenants who often rearrange their floor layouts.

    Toshiba SMMSi leads the industry with support for height differences of up to 40 meters between indoor units on a single system. That is enough height to cover an 11-story building. (As of December 2009, according to in-house studies)

    The versatility of the SMMSi means that virtually any configuration of the refrigerant Y-type branches and/or header piping can be used in an application to give the shortest, most cost-effective piping installation. The piping can be run in any direction to facilitate refurbishment work. Line and header branching after header branching are Unique Toshiba's systems!

    Toshiba active oil management system

    The active oil management system developed by Toshiba continually monitors the level of oil in all compressors, should an oil shortage be detected in any compressor, oil is automatically transferred from a compressor in another outdoor unit. The two compressors in an individual SMMSi outdoor unit are connected by way of an oil balancing pipe to ensure a uniform oil levels within the two compressors.

    1) Oil balance control. This control equalizes amount of oil between two compressors.

    2) Oil supply control. This control accumulates oil in the oil separator. When oil is insufficient, the system supplies oil to the compressors.

    3) Oil supply control between outdoor units. This control supplies oil accumulated in the oil tank of each outdoor unit to the outdoor unit with insufficient oil.

    Wide variety in SMMSi indoor unit line-up

    Внутренние блоки системы Mini SMMS ToshibaUp to 48 indoor units can be connected to a single Toshiba SMMSi system. There are 13 different indoor unit models available in 81 sizes. The large choice of indoor unit models and sizes compatible with the VRF range ensures the ideal solution for any application requirement.

    The performances of all units are maximised: low sound levels, optimised air flows and the extremely compact design that reduces installation time and costs. Moreover, the recent additions to the range, the compact high-wall and the slim duct units, reaffirm Toshiba’s commitment to create the perfect climate and well-being for business users. Toshiba provides the ideal climate and comfort levels, ensuring a healthy environment, high technology, maximised efficiency and modern design.

    All indoor unit are applicable for all Toshiba VRF systems (SMMSi, SMMS, SHRM and MiNi-SMMS).

    Toshiba SMMSi protection devices

    • Discharge and suction temperature sensors
    • Internal overload relay
    • Compressor over-current relay
    • Over-current sensor
    • High pressure switch
    • Low pressure sensors

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