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Ideal Air Loads, humidification and dehumidification not working

asked 2019-04-30 06:08:37 -0500

H's avatar

updated 2019-04-30 12:18:36 -0500

Hey, Im using OpenStudio 2.8.0 and try to use Ideal Air Loads to calculate the energy demand for space heating and cooling. I have added heating and cooling setpoint which works, and keeps my thermal zones within the temperature limits at all times.

It does however not control the reative humidity in the zones at all. I have made schedules for humidifing (30%) and dehumidifing (70%) and added the scheules in the setpoint schedules. There is no effect on the results.

Does anyone have any ideas what the reason for this might be?

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answered 2019-04-30 12:01:15 -0500

By default, the zone ideal air loads objects do not include humidity control. You'll need to use the Ideal Air Loads Zone HVAC measure or the Ideal Loads Options measure on BCL to model ideal loads and specify humidity control.

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Thanks for your answer! I've downloaded the Ideal Loads Options measure now, where I see the options for humidification and dehuidification control. When chosing the Control: Humidistat, the simulation fails however.

My other options are: System, heating, and cooling: always available. Heating and cooling: No limit. No DCV, heat recovery or anything else.

I've also tried running the simulation with Constant Supply Humidity Ratio for both Humidification and Dehumidification. Then the simulation works, and it adds humidity to my thermal zone. But as the name says, it does it constantly.

H's avatar H  ( 2019-04-30 22:41:10 -0500 )edit

Update: I've also tried Ideal Air Loads Zone HVAC. In this measure, Control: Humidistat, works. Or the simulation runs, but not giving me the results I want.

H's avatar H  ( 2019-05-01 00:20:44 -0500 )edit

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Asked: 2019-04-30 06:08:37 -0500

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Last updated: Apr 30 '19