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VRF with DOAS Measure Error from BCL

asked 2016-08-17 10:09:50 -0500

shopengarten's avatar

updated 2016-08-18 15:43:17 -0500

Got the following error while trying to run the measure:

/ApplyMeasureNow/UserScript/resources/OsLib_HVAC.rb:1181:in `setZoneforMasterThermostatLocation': invalid null reference Expected argument 1 of type openstudio::model::ThermalZone const &, but got NilClass nil (ArgumentError)

in SWIG method 'setZoneforMasterThermostatLocation'

Followed the instructions from this page: https://unmethours.com/question/18233... "Error Applying BCL VRF w/ DOAS Measure"

But still got the same error above.

Can't seem to resolve after deleting the existing HVAC system entirely.

Any help would be appreciated

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This error is occurring because in the measure the setZoneforMasterThermostatLocation method requires a thermal zone, and you aren't passing a thermal zone to it. There could be several reasons why it isn't passing a thermal zone. How many thermal zones are in your model? Could you link to a copy of your model so I can take a look at it?

mdahlhausen's avatar mdahlhausen  ( 2016-08-24 11:58:29 -0500 )edit

I went through the model and I have 22 thermal zones assigned to 22 spaces on 7 floors.

Is the measure looking for a master zone for each VRF system? Is that something I can assign prior to running the measure?

shopengarten's avatar shopengarten  ( 2016-08-24 13:54:03 -0500 )edit

perhaps you have an extra vrf terminal without a thermal zone assigned to it? Could you send a link to download the model on dropbox or some other file sharing site? That'd make it easier to help debug.

mdahlhausen's avatar mdahlhausen  ( 2016-08-25 10:36:52 -0500 )edit

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answered 2016-08-26 18:59:08 -0500

Ok. So I was able to recreate this error.

It occurs if there is only one thermal zone to add the system to on a given building story. This can happen if you only select a few spaces types in your model, or you have few zones in your model

Specifically, in the file OsLib_HVAC.rb in the resources folder, you need to change line #1181 from this:

vrfAirConditioner.setZoneforMasterThermostatLocation(thermalZonesToAdd[1])

to this:

vrfAirConditioner.setZoneforMasterThermostatLocation(thermalZonesToAdd[0])

If there is only one zone in the array thermalZonesToAdd, then there isn't a [1] object to access. Remember that ruby arrays start at index 0.

@david-goldwasser seems to be the author and can probably fix this in the OsLib_HVAC.rblibrary.

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Asked: 2016-08-17 10:09:50 -0500

Seen: 370 times

Last updated: Aug 26 '16