Re: [EnergyPlus_Support] RH control withint the limits

Hi Danko,

I looked at your idf file, and noticed the following two problems:

(1) for the minimum humidity control (humidification) you need to define a humidifier. There is an electric humidifier that needs to be added upstream of the Coil:cooling:water object. Your minimum humidity set point manager places the calculated humidity ratio setpoint on the outlet node of the humidifier. Therefore, you need to add a humidifier to see the minimum humidity control.

(2) you do not need the following input objects:

!SetpointManager:Scheduled,
!    HeatSys2 Loop Setpoint Manager, !- Name
!    MinimumHumidityRatio,    !- Control Variable
!    MinRelHumSetSch,         !- Schedule Name
!    HeatSys1 Supply Outlet Node; !- Setpoint Node or NodeList Name

!SetpointManager:Scheduled,
!    CoolSys2 Loop Setpoint Manager, !- Name
!    MaximumHumidityRatio,    !- Control Variable
!    MaxRelHumSetSch,         !- Schedule Name
!    CoolSys1 Supply Outlet Node; !- Setpoint Node or NodeList Name

the minimum and maximum setpoint managers: calculate the humidity ratio setpoints based on the humidification/dehumidifcation load of the zone and place the humidity ratio setpoints on the user defined nodes/nodelist in the minimum and maximum humidity setpoint managers objects. The humidication/dehumidification loads are calculated based on the Relative Humidities specified for the zone air. Therefore, the above schedule objects are not required and used incorrectly.

Also, run for typical winter and summer days until you resolve the problem.

Hope this helps you to start trouble shooting the problem.

Bereket

From: Danko Davidovic <ddavidovic@xxxxxxx>
To: "EnergyPlus_Support@xxxxxxxxxxxxxxx" <EnergyPlus_Support@xxxxxxxxxxxxxxx>
Sent: Wed, August 11, 2010 8:58:18 PM
Subject: [EnergyPlus_Support] RH control withint the limits

Hi all,

I am trying to incorporate the RH control of interior air into the model (see attached model). I built the model for single zone and followed the available recommendations in the documentation and online to setup properly the RH control of the interior space. I made the model up and running but do not see effect of incorporated control on RH profile in interior space. Would appreciate any suggestions or hints to go around this problem.

Thanks.

Danko Davidovic
Staff II - Building Technology

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