Question-and-Answer Resource for the Building Energy Modeling Community

Packaged Terminal AC (PTAC) Units

beopt
ptac

asked 2019-09-11 16:54:31 -0500

rbergepri
21 ●1

updated 2019-09-12 07:35:13 -0500

Aaron Boranian

13830 ●76 ●24 http://bigladdersoftware.com/

I want to model an apartment complex with PTACs that supply hotel style heating and cooling. Some apartments will have both 3/4 and 1 ton PTACs in the same apartment, but servicing different rooms. I have two questions:

Is BEopt capable of modeling a PTAC, and if so, which category under "Space Conditioning" would it fall in?
Is BEopt capable of having different sizes of PTACs in the same modeling run?

edit retag flag offensive close merge delete

add a comment

1 Answer

Sort by » oldest newest most voted

answered 2019-09-12 08:10:55 -0500

shorowit

10911 ●180 ●9 https://www.nrel.gov/b...

If the PTAC uses a heat pump for heating, use BEopt's Mini-Split Heat Pump category. Otherwise, use BEopt's Room Air Conditioner category (in combination with Electric Baseboard if the PTAC uses strip heat).
If you ask BEopt to autosize HVAC, it will calculate different sizes for each apartment. But if you hardsize the equipment, only a single size can be specified for all apartments. One option is to do two runs, 1 with 3/4 ton and 1 with 1 ton, and then combine outputs for the two runs by looking at unit-specific outputs. There is a dropdown on the output screen where you can see outputs on a unit-by-unit basis instead of the entire building.

edit flag offensive delete link

add a comment

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Careers

Question Tools

Stats

Asked: 2019-09-11 16:54:31 -0500

Seen: 225 times

Last updated: Sep 12 '19

Site design and logo: Copyright © 2015 Big Ladder Software LLC. All rights reserved.
The Unmet Hours and Big Ladder names and logos are trademarks of Big Ladder Software LLC.
User contributions licensed under the Creative Commons Attribution Share Alike 3.0 License.

Packaged Terminal AC (PTAC) Units edit