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Set-point manager in air loop (generic)

asked 2019-04-10 01:57:57 -0500

Fustrated gravatar image

updated 2019-04-10 07:34:15 -0500

Hello all, I have a detailed system with an AHU with a cooling and heating coil serving one zone. I'm combining a Single Zone Heating and Single Zone Cooling Setpoint Managers for the generic air loop, but I'm not sure if this is the best set-point manager to use... if I employ the warmest setpoint manager the gas consumption decreases quite a bit. Would using either of the set point managers (i.e. a Single Zone Heating and Single Zone Cooling Setpoint Managers or only using the warmest) be correct? Also, I do not understand very well if I use the warmest setpoint manager how the heating is controlled. Thanks a lot!

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answered 2019-04-24 16:45:28 -0500

The best way to model a system is to look at how it works in real life. Most rooftop units that serve a single zone have constant volume fans; therefore, the temperature of the air varies between a maximum and a minimum.

You can control your Airloop in this fashion using a SetpointManager:SingleZone:Reheat object. You will set your Minimum Supply Air Temperature and your Maximum Supply Air Temperature.

In your case, because you have a single zone system it does not make a difference to use the SetpointManager:Warmest to reset the supply air temperature, as there is only one zone and the SetpointManager:SingleZone:Reheat will also do that reset to accommodate your constant airflow.

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SetpointManager:SingleZone:Reheatshould be avoided, see: https://github.com/NREL/EnergyPlus/is...

Jeremy gravatar imageJeremy ( 2019-04-24 18:24:42 -0500 )edit

@Jeremy what would be your approach?

Luis Lara gravatar imageLuis Lara ( 2019-04-24 21:55:36 -0500 )edit

For a single-zone system, SetpointManager:SingleZone:Heating and SetpointManager:SingleZone:Cooling.

Jeremy gravatar imageJeremy ( 2019-04-24 22:45:37 -0500 )edit

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Asked: 2019-04-10 01:57:57 -0500

Seen: 100 times

Last updated: Apr 24