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How to Model Supply Air Temperature Reset?

Could someone please confirm if I am modeling my supply air temperature reset correctly for a LEED baseline model in OpenStudio 1.11? It should follow ASHRAE 90.1-2007 Section G3.1.3.12 which states, "The air temperature for cooling shall be reset higher by 5°F under the minimum cooling load conditions." My zone cooling setpoint is 75°F and the design cooling supply air temperature is 55°F. I am using SetpointManager:Warmest with the minimum setpoint temperature at 55°F and the maximum setpoint temperature at 60°F. image description

I am following other threads and documentation such as

https://unmethours.com/question/14152... http://bigladdersoftware.com/epx/docs...

kramerica's avatar
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kramerica
asked 2016-05-31 16:43:42 -0500
MatthewSteen's avatar
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MatthewSteen
updated 2016-05-31 19:55:52 -0500
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Plot the supply air temperature versus air loop flow rate and specific zone air flow rate to see how the HVAC system responds.

rraustad's avatar rraustad (2016-05-31 19:41:05 -0500) edit
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Correct, the SetpointManager:Warmest satisfies the PRM requirement. It's also how the OpenStudio Standards create the baseline systems 5-8.

MatthewSteen's avatar
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MatthewSteen
answered 2016-05-31 19:54:57 -0500
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@MatthewSteen What if I have two different setpoint for two thermal zones, connected to a single AHU?

Gio's avatar Gio (2017-08-01 04:09:05 -0500) edit

What setpoint manager is necessary for the heating coil in the above example? Heating room setpoint is 70F.

keb's avatar keb (2021-09-24 09:35:45 -0500) edit
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@Gio that's what the VAVR terminals (or zone equipment) is for. @keb the SetpointManagerWarmest controls both coils. During heating it's 55F and during cooling it is 55-60F.

MatthewSteen's avatar MatthewSteen (2021-09-24 10:32:30 -0500) edit
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