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Heat Rejection by VRF Condensing Unit

asked 2016-12-20 10:45:55 -0600

Ladan gravatar image

updated 2017-01-25 00:50:14 -0600

I am modeling an HVAC system, where my rejected heat by VRF condensing unit is used/recovered for heating domestic hot water. Do you know how I can get an hourly output of my VRF rejected heat in Energyplus?

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answered 2016-12-22 06:03:33 -0600

Jim Dirkes gravatar image

I think the answer that will serve you best is to review the .rdd (text) file after a successful simulation. It contains all of the Output:variables which apply to your simulation. Search for VRF-related variables and try them out. The .RDD file is invaluable, as are output:variables, for understanding results.

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Thanks for your help. The problem is that I do not see that output in my current settings for VRF.

Ladan gravatar imageLadan ( 2016-12-23 16:53:21 -0600 )edit

When you say "do not see that output", do you meant that you have opened the .RDD text file and cannot find any reference to VRF? Each time E+ runs successfully, an .RDD file is created. The name is yourfilename.RDD and it will be in the same folder as all of your other output.

If you are still having difficulty after checking that file, please attach your .IDF file.

Jim Dirkes gravatar imageJim Dirkes ( 2016-12-24 04:38:26 -0600 )edit

answered 2017-06-07 15:13:01 -0600

If you have created your water-cooled VRF system correctly by setting the AirConditioner:VariableRefrigerantFlow object's Condenser Type input field set to WaterCooled, and created a PlantLoop object to represent the domestic hot water system using the rejected heat, then you should be able to generate an output variable named VRF Heat Pump Condenser Heat Transfer Rate. This should add a column to your output CSV file to show the Watts of heat transfer that occurs between the refrigerant and the condenser water loop (in this case, your domestic hot water system).

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Asked: 2016-12-20 10:45:55 -0600

Seen: 262 times

Last updated: Jun 07 '17