Drawing Board Help General Information

Our Tale of Woe! Lesson Learned!

We are constantly preaching the wisdom of setting up defaults before starting any part of a project.

Well, as embarrassing as it is, we’re going to admit to not taking our own advice and show the results.

We were working on a fairly large and complex project that required a Manual J, Manual D and duct drawing and a Manual S. Obviously we used Drawing Board and MD Ductsize.

We worked our way through the drawing for the Manual J.  With a sigh of relief that the hard part was done, we started on the Duct.  And that’s where things went wrong. We were just a bit too cocky.

Here are the mistakes we made.

We put the Supply Main Trunk and all the other Supply Trunks into the drawing. Then we started adding the runouts for each room and attaching them to the trunks. Then we evaluated the project. Wait! The duct size and air flow didn’t show up.

Oh, I didn’t set the defaults to Show Flow and Show Size!

We’ll fix that. Right click on any duct, select General Duct Setting and then Multiple Duct Properties.


On the left select all runouts.

On the right, put a check next to Show Flow and Show Size and set both to True.




Okay, that got fixed. It took just a little bit of time, but it was relatively painless.

(We aren’t going to talk about the duct sizes. We had to change all those one at a time.)







Now, look at the fittings, starting with SR-270.

Wait a minute! It shows a Junction Box.  We’re not using that here. We need one of the Supply Trunk Junction fitting from Group 9 or a Balancing Damper. – Group 13.

If you look at all the runouts in the MD Ductsize drawing, they all use the Junction Box. But we only need them in a couple of places. That means we have to change them one runout at a time.

We could have avoided that problem if we had just set the Default Fittings before we started. Before adding the runouts, we should go to the General Duct Setting and Duct Default Setting for this System.

The Default Fittings for this System button is on the top left. Click on this button and you get a section to select the fitting you will use for most of the system. Then you only have one or two to modify.










If we practiced what we preached the project would have been done a lot sooner. Hopefully we learned our lesson.


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