OpenStudio EnergyPlus - VRF/VRV Curves Input

In this video we will use a custom spreadsheet to input equipment performance curves into OpenStudio. A copy of the spreadsheet and example documentation can be found here: https://drive.google.com/drive/folders/1z_dhmE3yO_WsVmwXdgi1wTb-3zVgF4bh?usp=drive_link Transcript: We are going to model a City Multi VRF system. Starting with the calculator spreadsheet; this is the output report that will be printed to the notes to the energy modeler. This contains all pertinent information associated with the VRF heat pump. Info that the energy modeler needs to account for. These are items that we cannot model directly; it is based on the energy modeler's specific project. They will have to modify these fields themselves. That said, we have a cut sheet for the equipment. These are all automatically generated performance curves that are being compared to the EnergyPlus default performance curves. There are one, two, three, four, five. Five input tabs that need to be modified to calculate everything in the spreadsheet. All of these other tabs are just calculations. They derive all of their data from these five tabs that we need to input. Starting with the OSM input tab you will see these are all the calculations. All of this is autogenerated based on these green fields. So, all we have to do is modify these green fields. In this tab, modify the green fields in this tab...actually these fields are derived from this table so...not this tab...we will get to this later. Then this tab there is also some green fields that need to be modified. And this tab as well. We need to modify these green fields. Everything else is auto-calculated. These do not need to be modified. Just the green fields. It is the same with the cooling tab. These green fields. Once all of those green fields have been modified, everything is automatically calculated on the OSM input tab. Finally, we will copy and paste these red fields to an OSM file. Then we can input it into an OpenStudio library. Let us begin. It starts with the specification cut sheet. This can be found in the city multi data book. We will be modeling the 144. That is going to be this one right here...we can just copy...just copy this page to a snapshot. Paste it. We are just going to overlay it over the top of this one here. Let us send it to the back. This is the older one. This is the previous one we modeled; the EP120. We are going to delete this. Now we have the EP144. We will adjust this to the correct, highlighted, parameters. Then, it is as simple as typing in these values. So, 40.4....12.72...12.70... Then the next step is to bring in this cut sheet. It can be found in the submittals. Let us see...it is going to be in the folder. Each one of these modeling objects has its own folder with performance curves. Open up the submittal for the EP144. Copy this page to a snapshot. Paste this in here. Something like this. We are going to send this page to the back. We will select the old 120. We are going to delete it. Now we have the 144. Again, just adjust this with this. Again, we need to input the data. It is 15% to 100%. 15% is already in there. How many compressors? This has one scroll compressor. This is already one. That is it for this page...let me see...yes that is it for this page. The next page we need to go to is the cooling page. First thing we need to do is edit the first green field...PUHY... Then, it is going to be a 144. This can be taken from this specifications cut sheet...but it is also on this curve sheet that we are going to copy from the city multi data book. Let us go to the city multi data book. We need to search for the EP144 performance curves. That is going to be this one right here. The first curve that we need to edit...well let us see...let us drop in the whole sheet first. We are going to take this sheet and copy the snapshot. We are going to paste this in here. We will send this to the back. We are going to delete the old EP120. Now we have the EP144. Now we need to change this field. It is going to EP144TNU/YNU-A1. Then we need to change the rated performance values. This is going to be 144,000. The cooling (output) is going to be 42.2kW. The input is going to be 10.63kW. The next step is to digitize the next curve and input these values. I use a curve input algorithm...let us see...it is going to be the plot digitizer software. Right here. I have purchased the plot digitizer software so I can use it on my computer. If you want to, you can use the plot digitizer online. Go to plotdigitizer...and just open up this link...plotdigitizer.com. Click the free online app. Plot digitizer takes an image and then you can extract data points from that image. We will be taking this first image here. This is going to be the indoor unit temperature corrections. They are from this chart right here. ... Complete transcript: https: //www.helix-engineers.net/technical-articles