This article explains how to label your ducts and diffusers using metric units. It requires changing a few settings in the Options dialog box.
You still do your design in imperial units. One unit on the drawing should be one inch. All ducts will be sized to even inches. This options will only change the units of the labels.
Start by opening the Options dialog box. Go to DM HVAC->Customization->Options. To make changes to the labels for the current project, use the Edit Project List command. To make changes for future projects, use the Edit Standards List command.
Ductwork Size Units
Go to the Ductwork section. You want to change the Rectangular duct label format, Round duct label format, and Oval duct label format options.
There are three different ways to convert the labels to metric. You can convert to centimeters, millimeters, or soft millimeters. Soft millimeters will convert 1 inch to 25 millimeters.
This article will describe changing to the soft millimeter conversion. If you want one of the other conversion choices, see the Duct Label Format Codes section of the user manual for information on what values to use.
Change the options to the following values:
- Rectangular duct label format: WMMSxDMMS
- Round duct label format: DMMS%%C
- Oval duct label format: WMMSxDMMS%%C
Diffuser Airflow Units
Go to the Diffusers section. You want to change the Diffuser CFM label format option.
- Diffuser CFM label format: $LPS
Updating Your Drawings
To update your ductwork sizes, redraw the ductwork.
To update your diffuser labels, run the Coordinate Drawings and Database command.