This is an app to dimension an Yanmar air conditioning system, consisting of indoor units in rooms, connected to an outdoor unit outside a building.

Using a given room load, this app selects the indoor units covering this load, calculates all technical data about those them and draws the piping and wiring diagrams showing their connections to the outdoor unit.

As air conditioning devices become ever more sophisticated, their manual selection is no longer obvious. This app takes all aspects of device selections into account:

  • It selects indoor units taking the cooling (total and sensible) and heating loads into account.
  • It calculates the piping diameters with possible diameter size ups and the required amount of refrigerant.
  • It supports the selection of options and calculates a complete equipment list.
  • It draws a piping diagram, a wiring diagram and a centralized controller diagram.
  • It creates reports in MSWord documents (Windows and MacOS only).
  • It supports both SI and imperial units.

An Yanmar air conditioning system may consist of the following devices:

  • Outdoor unit. An outdoor unit provides the cooling or heating capacity for several indoor units. Depending on the number of indoor units in a building, you may need more than one outdoor unit. There are two kinds of outdoor units: heat pumps and heat recovery. Heat pump outdoor units provide either cooling or heating for all of its indoor units. Heat recovery outdoor units provide an automatic change-over of its indoor units, through the use of BS units.
  • Indoor units. An indoor unit provides the cooling or heating capacity in a single room, Depending on the size of the room, you may need more than one indoor unit. Indoor units can be mounted in the ceiling, on the ceiling, on the wall or on the floor. It may blow air directly in the room or through ducts.
  • BS units. A BS unit automatically changes indoor units connected to them from heating to cooling and vice versa, depending on the demand in the room.BS units are connected to heat recovery outdoor units.
  • H branches. A H branch has up to 8 pipe connections.. You select a H branch in the same way as devices and the app adds it to the tree view. Then you connect either indoor units or BS units to it.
  • Y branches. A Y branch has two pipe connections. The app automatically inserts the necessary Y branches when producing a pipe diagram.

This app automatically dimensions the indoor units, BS units and outdoor units, depending on the required cooling or heating loads.
It also detects selection problems immediately. By using a tree representation, the user gets an overview of the systems to design. Selecting an element in that tree promptly gives information about that element.

To support a step by step design, the app offers a number of sections. Each section supports some specific actions:

  • Manage Projects. ManageGives an overview of existing projects and offers several file and folder operations.


  • Define System. SystemOffers commands to define outdoor systems with their BS units, indoor units and H branches, organized in a tree view.


  • Piping Diagram. PipingDraws a piping diagram for an outdoor unit with its devices and allows defining piping lengths, number of bends and height differences. Calculates the length correction, diameters, possible size up and the extra refrigerant.


  • Wiring Diagram. WiringDraws the wiring diagram, allows selecting options and defining control groups, that is, one remote controller controlling several indoor units.


  • Central Wiring. CentralDraws a diagram showing the outdoor units connected to central controllers.


  • Tabular View. TabularShows the indoor units in a tabular view and organized per outdoor unit.


  • Reporting. ReportingCreates an MSWord report, containing the same tables as in the tabular view and extended with the diagrams (piping, wiring and central wiring). Reporting is only possible for Windows and MacOS.


  • Units. UnitsOffers different dimensions for units such as temperature, length, diameter, weight, capacity and airflow.


  • Preferences. PreferencesDefines name prefixes, numeric and date conventions, alternative diameters and tolerances. Allows changing personal data and the user interface language


  • Color setting. PreferencesDefines all colors that you can change in the user interface and in reporting


This app is about to be launched for Europe, Australia and U.S., planned for the first quarter of 2018.

You can find more about Yanmar air conditioning systems here