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Packaged Terminal AC (PTAC) Units

beopt
ptac

asked 2019-09-11 16:54:31 -0600

rbergepri
21 ●1

updated 2019-09-12 07:35:13 -0600

Aaron Boranian

14250 ●86 ●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?

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answered 2019-09-12 08:10:55 -0600

shorowit

11931 ●203 ●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.

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Asked: 2019-09-11 16:54:31 -0600

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Last updated: Sep 12 '19

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Packaged Terminal AC (PTAC) Units edit