Learn how to create MEP systems to define logical relationships between related elements in a model.
| Term/Concept | Definition |
|---|---|
| System | A set of logically connected elements. For example, a supply air system might include duct, fittings, diffusers, and mechanical equipment. |
| System Classification | A parameter that defines the system for the connectors that are located on air terminals, equipment, and fixtures. For example, an air terminal could have a system classification of Supply Air, Return Air, or Exhaust Air. These values are pre-defined classifications within Revit. |
| System Type | A parameter that defines the systems for an MEP system. For example, a duct system could have a system type of Supply Air, Return Air, or Exhaust Air. You can duplicate an existing system type to create additional system types as needed for the model. For example, if you need a system type for high pressure supply air, duplicate the Supply Air system type, rename it, and change the properties as needed. |
| System Name | A string that uniquely identifies a system. It may be user-defined or automatically generated. |
| System Browser | A tool to display a hierarchical list of all the system components in each discipline in a model. |
| System Inspector | A tool to modify, inspect, and view the instance properties for a selected duct or pipe system. |
| Generate Layout | A tool to specify slope and routing parameters for ductwork and piping, to view different layout solutions, and to manually modify layout solutions for a duct or pipe system. |
This video demonstrates how creating systems in Revit is a key step in automatically generating layouts, sizing duct and pipe, and performing calculations and analysis in the design.
When you create a system, you create a logical relationship between related elements in a project. For example, a supply air system might include duct, fittings, diffusers, and mechanical equipment.
Elements with connectors, such as air terminals and equipment, are assigned a system classification. For example, a supply diffuser has a Supply Air system classification.
You can select a group of diffusers and assign them to the Supply Air system type. Revit assigns a system name, or you can enter a new name.
If the default system types do not suit your needs, you can also create custom system types. From the System Browser, select a system type, then duplicate and edit it.
Next, select the equipment for the system. The equipment provides the supply for the fluid in the system, and is necessary for computing a pressure drop for the system and for using the System Inspector.
In this example, a heat pump is added to the system. Notice that the heat pump has more than one system classification. It is assigned to the same system as the diffusers: Mechanical Supply Air 36.
You can manually connect equipment and diffusers by placing the duct yourself, or you can use the Generate Layout tool to add the duct.
Assigning elements to systems also allows you to size duct, perform calculations, generate pressure loss reports, and use analytical tools in the design.