Humidity control not achieved in openstudio

Hi all, I am modeling a 5 story medium sized office in Tampa. HVAC system is a multi-zone single duct constant volume with no zonal reheat. The humidity and the temperature are controlled by the cooling and heating coils itself. I designed the HVAC system as district cooling and heating and have the humidity controls and setpoints (and managers) in the system as described here and set the sensor and actuator nodes as described in this link. The temperature controls are working perfectly with cooling and heating unmet hours within the recommended standards, but even with humidity controls, zone humidity values are all over the range. I'm not sure what is wrong, could someone point me in the right direction? I have attached the openstudio model files in this link.

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@akr could you post a link to your model?

Avi (2018-08-20 02:47:21 -0500) edit

@Avi Here is the link to the compressed zip files of the model. https://uploadfiles.io/w8exn

akr (2018-08-20 05:38:51 -0500) edit

Hi @Avi, have you had a chance to look at my model?

akr (2018-08-20 11:23:03 -0500) edit

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From a short glimpse at your model I believe that your Cooling and Heating Schedules are not working as you meant it to work. If you look inside those schedules you will find out that they are having only the default values through out the year. The reasons for that is that you forgot to select the days to apply the priority 1 and 2 day schedules. One other issue is that both priority 1 and 2 day schedules are valid all through the year while I think you wanted them to be summer or winter only.

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you set the Heating temp of all of your zones to 10.6 Celsius and Cooling to 30.1 Celsius. With that most of the time the temperature of your zones will run free and you can't control the humidity.

I believe that after you will correct that you will see better results

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Avi

answered 2018-08-30 03:49:26 -0500, updated 2018-09-11 03:46:17 -0500

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@Avi: Thanks for your response and time. I selected the default set point values throughout the year because this is an University building with district cooling and heating. As per the University's Facilities team, the thermostat set points doesn't change between weekdays and weekends. With respect to your response on priority profiles, even if we select a specific date range for the priority rules, do they still get applied to the entire year? Then what would be the purpose of a date range? Please let me know what you think.

akr (2018-08-31 10:39:33 -0500) edit

@akr So you set the Heating temp of all of your zones to 10.6 Celsius and Cooling to 30.1 Celsius. With that most of the time the temperature of your zones will run free and you can't control the humidity.

Avi (2018-09-03 13:20:05 -0500) edit

@Avi Thanks for the response. I think that pointed me in the right direction to figure out the issue. I will let you know how the results turn out. Thanks again.If you want to modify your original answer, then I can go ahead and mark that as an accepted answer.

akr (2018-09-10 13:57:07 -0500) edit

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Humidity control not achieved in openstudio

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Humidity control not achieved in openstudio