27 - WSHP, UFAD, chilled beams and more

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Hi everyone, again. This is Harshul Singhal. For this session we are going to work on some complex systems. Something like, water source heat pump. Or, maybe, chiller beam system or radiant heating and cooling system. We created a complex system recently, which was fan coil unit system with dedicated outdoor system.

I'm going to show you water source heat pump now, which is like, it has exactly the same workflow that we had for fan coil unit system. This time we'll have different zone equipment. If I go back to my OpenStudio model, which I created recently, I can save it as a different version.

Let's say, let's save it as, August 22 10am DOAs with water source heat pump, okay, save it. If you are not familiar with water source heat pumps, basically they are a traditional ASO heat pump except that it extracts and dissipates heat by way of water instead of air. Traditional air source heat pumps get the heat from the air outside. Although, these water source heat pumps, they dissipate and extract the heat from, let's say, a lake, lake source, or maybe from a pond, or something which has water in it, right. A very good example is Ithica, it isn’t Ithica, Cornell university, it actually uses Lake Cayuga as lake source. It actually extracts and dissipates the heat at the depth of this lake, okay. The lake temperature is constant, somewhere around a range of 55 to 65 degrees Fahrenheit at a depth of 60 to 80 feet I think, for this particular lake, okay.

For this class I will show you how to make changes to an existing HVAC system VRF fan coil system and zone equipment. What I'm going to do is, I'm going to keep the exact same air loop for ventilation requirement. All I'm going to do is, I’m going to change the zone equipment to water source heat pumps, connect it with them associated plant loops, and then, in this simulation, okay. If you have something like, water source or water lake as a source for extraction and dissipate of heat. What you need to do is, you need to create either a loop, a separate loop with infinite capacity for cooling, as well as for heating. Or, you can just attach them to the generic chillers or hot water boilers. But, then you need to manipulate with their efficiencies, as well as the capacity, okay. Again, there are different ways to do it, I'm just going to show you that easiest way, which is, just assume water lake as a district heat and district cooling source with infinite capacity, okay. If it's district heating and district cooling it's going to be 100% efficient, okay. It actually works, kind of ideal air load, okay. But, a lot of times, your facility managers can provide you different inputs for efficiencies and other things. The method that I am going to show you, is the easiest method. But again, you have to manipulate, or you have to customize your own HVAC system based on your design, okay, all right.

What I am going to do is, I'm going to just delete these FCU systems first. Just click on these FCUs, like, one by one, and it will take some time. You can just start from scratch if you want, but I really want to use the existing loops. Just trying to save my time, okay. I can just click on this cross here, select this FCU1-3, click on this cross mark here, on the top right. Do it for each and every FCU, okay. Will take some time, but let's just finish it, okay. There are some more of them here on my energy model, so, just going to delete all of them, okay. Again, the process is very simple, exactly the same with what we did for a FCU systems. But, this time, the zone equipment is going to be different. When I delete these FCU systems in thermal zones, it will automatically delete the associated heating and cooling coil for me, okay. Before I install the new zone systems, like water source heat pumps, I want to QC whether my associate heating and cooling coilsare also gone, okay. Click on this next tab. Go to your chilled water loop. You can see there is one more FCU-1 cooling coil, okay. And, if I go back to my hot water loop, there's another free-floating heating coil, which belongs to FCU1-5. Again, it makes sense right.

Like, I QCed it and then found that there is one more FCU that I need to delete, okay. Delete it, and now we are good to install the water source heat pumps, okay.
Go to library. Look for the water to air heat pump, this is what we are looking for. There are lot of options. Something like, electric backup, gas backup, and hot water backup. We want something like, hot water backup, which makes more sense, than something like water heater heat pumps. There are a lot of other options. I'm going to use this simplest one, which is, water to air heat pump with hot water backup. Drag it and drop it to one of the thermal zones. Let me just go back to the first one. Go to this thermal zone, drop it here, in this zone equipment column. Click on this. Rename it to, let's say, WSHP1. And then, you can start editing the properties. You can change schedule if you want, you can hard size that. If you scroll down, you can change a fan replacement. Right now it's blow through, you can actually change it to something like, draw through. You can change the maximum outdoor dry-bulb temperature for supplement heat operation. The fan values, you can change it to, let's say, F1. You can rename it, you can change the efficiency, let's say, 85 percent. You can change the pressurize, let's say, 0.25. You can change the flow rate and all. There is a curve for your fan, the efficiency curve. What else do we have. The very important thing is, you need to work on this heating coil for this water source heat pump, okay.

You can change the coefficient. This is the coefficient of performance for the heat pump coil, okay. Remember, we are not talking about backup coils here, we are talking about the heat pump coils. Again, you need to provide some COP value for this. You can get these values from your manufactures. Let's say this value is for 0.5. You can hard size it based on your manufacturer data. You can change the coefficients, the efficiency coefficients, okay. Right now, these are some default values for a heat pump. Looks fine to me for now, I'm just going to keep as it is. Next one is the heat pump cooling coil, okay. Again, you need to provide the coefficient of performance. Let's say it's 4.25, default value is 3, which is also like, you know, reasonable.

You can change the coefficients for your performance, like, I'm sorry, the efficiency. Then, the next thing is the backup coil. These are the backup coils, you can see. You can rename it if you want. You can change the capacity. You won't see any efficiency values there, because they will be connected to your boiler, okay. You can change the rest of the information.
The next thing that you need to do is, you need to click on these linkages. Click on the first link. It asks you, hey, like, you know, you want to attach the heating coil, the water to air heat pump heating coil. Right now, I don't have any hot water loop, which has some kind of district heating on it. I don't want to connect it to the generic hot water loop, because it's going to have its own efficiencies and its capacity. I'm going to connect this hot water loop to the backup coil. Or, even with the dedicated outdoor system hot water coil. Go to next linkages. It asks if you are connected to the cooling coil. Again, I don't have any district heating and cooling. The next one is, the backup heating coil, okay. I'm going to connect it with hot water loop, okay. And before I move further, before I copy this water source heat pump to each and every loop, the next thing that I want to do is, take care of the heating pump, heat pump, cooling and heating coil, okay.

Go back to your next tab, which is HVAC system tab. What you can do, you can actually create two separate water loops. One for district heating and one for district cooling. If I go to a plus sign here, and scroll down to empty plant loop, I can rename it to something like, district heating. Or, you can rename it to Lake, whichever you think is feasible for you. I like to rename, I like to model my water source heat pump with infinite capacity of district heating and cooling. There are different ways to do it. I'm just trying to show you the easiest way, here.
And then, what I can do, I can just like, you know, size it if I want. If it's heating 182, this this value looks fine to me. And, the next thing that I want to do is I want to drag, I want to scroll down to find district heating, okay. Just drag it and drop it here. Exact same process, you're going to have a pump. In case you don't have a pump in real life, you can just, like, bring any reasonable pump and change the flow rate to like, minimal amount, or change this power consumption to, let's say, 0 watt, in case there is no pump, okay. But, for the water loop, you have to have pump loop, even if it's a dummy pump, okay. You can change the capacity of this district heating, this number is quite big. Looks reasonable to me. You can auto size it, if you want. Let’s just auto size it and make things easier. Or hard size it, it doesn't matter, okay. This value is so big that it will take care of your infinite capacity, okay. The next thing that you want to bring is the schedule manager. Exact same process. I'm going to bring this hot water temperature value. You know the process you just need to change the hot water temperature value. I know that one of the existing hot water temperature schedule is for 180 degree Fahrenheit. I'm going to check that option.

The next thing is, you need to bring the demand side equipment. Go to my model, or, actually, you know what, don't worry about this for now. Create the next loop, which is the district cooling loop. Go to plus sign again, empty plant loop. Exact same process, district cooling loop, flue type is fine. You can just go to sizing, change this option to cooling. Design loop temperature can be 56. Or, if you think it's very high, change it to a reasonable value. Again, this district heating value also looked very high to me. For, I'm sorry, the district cooling value, I'm sorry, the district heating value that we selected here, for schedule manager, looked very high to me. But, you know the process now. You can change as for your own design. I'm just going to show you the process really quick for now. The district cooling loop, I'm just going to bring this existing deck temperature again, you can customize the value. Again, I need to bring a district cooling component here at the supply side. Go up scroll to D, look for district cooling. This is here. Same thing, drag it and drop it. Change the capacitor if you need to.

The next thing is a pump. Go to available speed pump, drag it and drop it. And, let's save my pump consumption, like energy consumption for pump is 0. I'm just going to hard size to 0. Then, if it's 0, then you not to worry about the rest of the inputs there. And the next thing is, I want to bring the demand side equipment. The easiest way that we have is, just either go to my model, drag it, drag the components from there and drop it here at demand side. Or, the one which I like to use is, go to thermal zone, again. Go to WSHP1. Click on the first linkage, here. It asks you to connect it with the district heating loop for this main heat pump coil, the heating coil. This is the backup, this will not be back up coil, mind you. This is the actual heat pump coil. Connect it to this district heating. And, next one is cooling, connect this district cooling loop, okay. And now, just like, copy this exact same order of heat pump to the rest of the thermal zones. I'm just going to select all of them. And then, I will use this apply to selected option here, which will reduce my workload significantly, again.

Once it's done, I will QC it one more time, okay. You can see that the software is taking care of a lot of things here. That's why it takes some time to run these scripts in background, okay. If you go back to your loops, let's say DC loop, you can see all those heat exchanger coils, here. Go to your district heating loop, and you can see all those like, heat exchanger, heating coils here, okay. Which makes sense. I can go to a simulation tab and run this simulation and it should work, okay. If it works, well and good. If it doesn't work, we can just look at the error messages. Definitely you want to make sure that your model works fine before you move to the next step. It's the very important QC, quality check, process that you should do for your energy models, okay. Looks like it's working fine for me. I'm just going to finish this simulation, shouldn't take more than 30 40 seconds.

I'll wait for it and then I can show you the results. How they look like, do I have some unmet load hours. If yes, there is a certain process to fix it. Like, most of times when you auto size your systems, chances are you won't get a lot of unmet hours. But, when you hard size systems, or you change the values of properties, then yes, there are chances of getting very high unmet load hours. You can fix them. You can increase the capacities. There is a whole documentation that you can search online to figure out how to take care of your unmet hours, okay. I'm not going to spend more time on that process. I'm just going to wait for my OpenStudio model to finish this simulation. And then, I will show the next method, which is, to run the OpenStudio measure to create a water source heat pump. Again, exact same process. We can spend maybe like, a couple of hours to create this kind of system, like, complicated system, like water source heat pump. But then, the easiest way is to just remain OpenStudio measure, finish it. Like, very easy process.

I will just run through a chill beam system again, real quick. I won't create everything from scratch. I want you to understand the process. Run the simulation by yourself, create the systems, and then run the simulation, sorry. And, reach back to us for your problems. We will definitely help you out. But, I don't want you to, I don't want you to just follow me, what I am doing here. I want you to understand the process, create the system by yourself, and then approach us, okay. If I go to my simulation, I'm sorry, the result tab, you can see I have some like, you know, KBTU per square feet number. I have an energy consumption for electricity and natural gas, everything. And then, I have reasonable amount of unmet load hours, which is fine. It means my system worked, okay. If I go back to my H thermal zones, I can look for other options here for zone equipment. You can do something for radiant heating and cooling. Exact same thing, you just need to bring your radiant systems here. And then, connect it to your chiller and chiller loop, as well as, hot water loop. Basically, a chill beam system or radiant heat system will work similar to what FCU system was. You need not worry about creating a district heating
and district cooling system, okay.

You can connect those zone equipment’s, like chill beams or radiant systems, to your main hot water or chilled water loops, okay. I want you to practice those systems by yourself, and reach back to us if you find any trouble. You have those baseboard systems, electric, as well as motor systems. Please try them by yourself, okay. For now I am just going to run the simulation. Run the OpenStudio measures to create water source heat pump for you, as well as radiant systems for you, okay. I'm just going to show you a quick demo, here. And, in case, in future you find any trouble creating these systems manually, you can just run this simulation, I’m sorry, run the OpenStudio measures. And, understand how your loops look like, okay. And then, try to copy those loops by yourself, okay. You will learn a lot of new things if you follow this process. If I go to whole systems and look for something, let's say, HVAC,water source heat pump, okay. This one, HVAC water source heat pump with dedicated outdoor air system. Apply measure.

And, remember, I did not delete my existing air loops and water loops. I'm just trying to run these this OpenStudio measure on top of my existing systems. Let's see if we find any issues, okay. The initial condition was, my building had 1 air loop and 5 plant loops, 18 zones were conditioned. The final condition is, my building has 2 air loops now with 2 plant loops. Very interesting, it actually deleted 3 plant loops for me. And, one of them was domestic hot water system. I'm very curious now, what it did for me, okay. I'm just going to accept the change, and go to my, I mean, first let's see, is this thermal zone side, okay. You have those air loops, make sense. Then you have those water to air heat pumps that we also created in the manual method. Let's go to the HVAC systems. I know it has created a single water loop for us, for district heating as well as for cooling. And, it has created a very interesting schedule manager method, set point management method. It has created scheduled for two components two supply components. You can see those air loops here, like, dedicated outdoor system air loops. This time we have a cooling coil DX single speeds. There is no need of a water coil here for cooling. Same thing with this heating furnace. You can always change them to water affiliate systems.

The next thing I want to check is this heat pump loop. Alright, you can see here, I think we ran something else. Or, actually, you know what, it created a new system, if you remember. I asked you to create those, I mean, you can also create those hot water boilers, as well as those chillers in district heating and cooling. You can just change their efficiency in everything. There is another method. See, it created these notes for you. These interesting set point manager notes for you. Control variable is again, temperature, but that created the schedule, separate schedule. It had created a hot water temperature schedule for boiler, and a separate set point manager for cooling, okay. You can check those temperature values. And, it has a separate schedule here, as well, for loop temperature, okay. It's very interesting. I can explain you this, but I really want you to QC this plant loop by yourself, okay. The process is exactly the same. It's a bit complicated than what I created for you. I created the easiest for you, incase, initially if you are not very comfortable with creating the complex systems. Just start with the easiest process and then jump on this complicated system, okay.

Looks fine to me. If you run this simulation, it will work. I'm going to run another OpenStudio measure for you. Let's create a radiant heating and cooling system this time, okay. I'm just waiting for that screen to pop up for me. It takes some time, sometimes. Go to HVAC, whole system, and look for some radiant system, okay. This one, HVAC radiant dedicated outdoor system, run it, okay. These are the very, like, these are the easiest possible OpenStudio measures that you can download for free from BCL library. We have our own complicated and sophisticated version of these measures. Feel free to contact us if you want to, okay. Again, now it has created additional loops for me, make sense. I'm going to accept the changes. And, if I go to my thermal zones. Guys, looks like the model crashed on me. And, it happens a lot of times when you actually run those OpenStudio models on top of some, like, unnecessary information.

For example, I had some unnecessary information related to HVAC system. And, I ran this the OpenStudio measure, and it crashed on me. And, that's why I asked you to delete the existing information always, okay. I'm just going to open my file, again. Again, it's a process, but here, you need to go through it. That's good that it crashed on me. Now you understand why you don't want to keep additional information in your energy model, okay.

I'm just going to open the one of the existing OpenStudio models, which I saved maybe like, 15 minutes back. Let's say this DOAs with water source heat pump, open it. Discard, yes, it's fine. And now, just go back to your HVAC systems, delete the existing information, or, let me actually first save the model, a new version of this model. Let's say, DOAS with radiant systems, okay. Save it, and then delete the existing loops and the thermal, I'm sorry, this zone equipment, okay.

Once you are done with deleting these loops, go to your thermal zones, and start clicking on this ideal air load, it’s the easiest process, trust me, okay. It will delete all the unnecessary information that you want to delete from your project. And now, run that radiant measure, okay. Radiant OpenStudio measure. These OpenStudio measures, as I mentioned earlier, they're so versatile. You can do so many things here, within seconds, or within minutes, okay. This time I'm going to run this radiant measure. I hope this works on this clean model, let's say. Just running measure now. I should have saved the model, actually, it did say for me. We should get exactly same final condition that we saw last time, okay.

Now we have 2 air loops and 4 plant loops, make sense. Accept the changes, and then click on
one of the existing radiant zone equipment, okay. And, awesome, you can see, we have those radiant systems in zones now. You have some values like, you can provide the schedule when you want to make it available. Radiant surface type, you can change to either floor, ceiling, or all surfaces. It's totally up to you. You can change the tubing diameter. You can change the tube in length. Control type is mean radiant temperature, which makes sense to me. But, you can change with some other properties like, outdoor driver bulk temperature, operative temperature, and all, okay. Then you have those heating coils. The variable flow, that radiant temp, radiant heating coils. You have totaling range, you are scheduled to provide same with cooling coil. And, that's it. And now, you can connect these cooling, heating coils to your existing plant loops. You can see this heating coil is connected to radiant hot water loop. And, same with cooling coil, it is connected to radiant chilled water loop. Exactly same configuration for each and every radiant flow.

And then, on top of that, we have this ventilation requirement dedicated outdoor air system air loop. Click on the next tab, find this hot water loop. You can see this, they're only two coils there. They are connected to the air loops it seems, those ventilation requirement heating coils. If you go to chill water loop here, which is just one chill loop, you can see all those radiant cooling coils, here. You can see they are all connected to those zone equipment that we have in our thermal zone tab, okay. I'm trying to find one chiller loop for main cause. Seems, okay. Make sense. That version, that OpenStudio measure version, the default one that you downloaded from BCL, it actually creates a DX single speed cooling coil. Well you can actually manipulate it. This existing system, it's very easy, you can just delete this existing one. Go to water coils, bring it here, drag and drop. And, just go back to your radiant chill water loop. Go to my model, and drag and drop this new cooling coil, okay. Easy, very easy process, okay. We have 1, this ventilation requirement air loop cooling coil. And then, the rest of these are the radiant cooling coils.

If you go back to your hot water loop, same thing here, 2 main coils. But, this measure actually created a separate hot water loop for your radiant heating coils, which is kind of weird, I don't like this. Like, what I can do, I can just go to my model, look for heating water coil. Drag it and drop it in this plant loop, the one which already has those existing radiant heating coils. And then, you can go back to this hot water loop, and delete this empty plant loop, it's basically doing nothing, just delete it, okay. Again, those measures are helpful, but you should always QC them properly, okay. For example, if you click on this, on the dotted line, they are sized for 100 person heating and cooling for outdoor air. Let's check it. Looks like the minimum system air flow ratio is 1, which makes sense. And, it's 100% outdoor air in cooling and heating, yes. It's fine. But, you should always QC your components, okay. Don't just completely rely on those OpenStudio measures. Automation is good, but always, a QC is necessary, okay. Looks like we have created a radiant cooling and heating system, which is awesome. We can save this, and when you run this simulation it will work, okay.

We worked on fan current system. We worked on water source heat pump. We worked on radiant heating and cooling system. Underfloor heat distribution. You can do a lot of other things. You can create ground source heat pump, you can create air source heat pump. You can create chill beams. I would suggest you to run those OpenStudio measures by yourself. Understand the systems, and then try to create them manually. And, if you find any trouble or any issues or any questions, please raise them. Please write us an email on info@simulate.energy. Or, you can always leave a comment under this video. We will try to reach back you back to you as soon as possible, okay. In our next video, we learn more about the VRF systems. Thank you. Bye.