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OS: VRFwithDOAS failed

asked 2018-10-08 22:52:10 -0500

Mantra gravatar image

updated 2018-10-09 07:02:10 -0500

Hi all,

I am trying to design DOAS system to my existing VRF system in OS. I have successfully designed the VRF system (1 terminal 1 thermal zone). Would like to put 5.5 l/s/person precooled outdoor intake to the room, and found out that designing the air loop coupled with VRF in OS is not easy, I tried to use the measure in BCL "VRFwithDOAS". My model is simple 1 thermal zone building. And never ran successfully. Always show this message: image description

It says the error is "Null reference for setZoneforMasterThermostatLocation", but i couldn't find any clue where to input it in the VRFwithDOAS measure, anyone can help me with this?

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can you add more details about your OpenStudio model. How many spaces are there? How many thermal zones? What thermostats have you set on the Thermal Zones?

TomB gravatar imageTomB ( 2018-10-09 05:14:39 -0500 )edit

Only a simple one room building. 1 space, 1 thermal zone, the thermostats I set in 24oc

Mantra gravatar imageMantra ( 2018-10-09 20:36:43 -0500 )edit

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answered 2018-10-09 11:51:57 -0500

This was previously answered on the forum here.

There is an NZE HVAC measure that includes VRF and DOAS and will be posted to BCL after the OS v2.7 release this week. That includes more realistic DOAS controls and VRF coefficients.

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Asked: 2018-10-08 22:52:10 -0500

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Last updated: Oct 09