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OpenStudio producing incomplete IDF: PlantEquipmentOperationSchemes

asked 2015-02-24 17:25:23 -0500

updated 2015-07-11 17:16:26 -0500

I could provide an osm example where OpenStudio 1.4.0 crashes, and OpenStudio 1.6.0 produces an idf file (out.idf) which is incomplete and subsequently simulations fail. The osm model contains 3 plant loops (two connected: heating and hot water, and another for hot water). OpenStudio 1.6.0. does not produce complete plant equipment lists etc., however after manual editing, the simulations are completed sucessfully. (No guarantee that the results are reliable).

This is a potential bug in OpenStudio.

Is the this forum the right place to upload detailed models or should such reports rather be sent to ?

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answered 2015-02-26 09:58:00 -0500

You've come to the right place! Can you upload your model to a drop box for us to review? OpenStudio categorizes equipment by control type (heating / cooling / uncontrolled) to locate it on the appropriate equipment list. The most likely scenario is that a particular type of component was allowed on the plant but not categorized for an appropriate equipment list.


I received your model and found that "Plant 2" did not have any supply equipment.

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I took a guess and figured that you wanted that heat exchanger to draw heat from one of the other hot water plants, so I rearranged things so that the heat exchanger is a supply component on "Plant 2" and a demand component on "Plant 1". I also found that your pumps were located on the demand side of the plants which is incorrect, unless you were trying to do a primary / secondary setup, so I moved them to the supply side. It now looks like this.

image description

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I didn't investigate your control options, so I can't guarantee that this is running exactly the way you want it to, but this should get you on the right path. I'll send the adjusted model back through email.

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Excellent, thanks ! The real system to model, by the way, was a wood gasifier with hot water buffer tank as a water heater, where heat exchanger in reality is built-in to the tank for DHW production. Therefore the only change I now would try is to have a different SPM for the HW baseboards and for the heat exchanger (which should be fed by higher temperatures, essentially the tank outlet temperature, which is why I tried to insert the heat exchanger right after the water heater). The next model improvement would be to use a stratified water heater.

OS-user-AT's avatar OS-user-AT  ( 2015-02-26 15:28:55 -0500 )edit

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Asked: 2015-02-24 17:25:23 -0500

Seen: 152 times

Last updated: Feb 26 '15