GPG Outbrief 14: Variable Refrigerant Flow
Hello. Everyone and welcome to today's webinar on variable, refrigerant flow, we're, going to get started very shortly but before we do I'm going to go over just a few webinar. At logistics. My. Name is Andrea Silvestri, and we, have a great a great lineup today of, speakers, and presentations. So. Today's webinar. Will. Include, an, overview, of a report by Pacific, Northwest, National Laboratory, and, this, report, the full report as well as a four page findings, and one-page, infographic. Are available. At gsa.gov, slash. GPG, and you, can find additional, resources. Here, as well. Today's. Webinar is one in a series we'll. Be taking a break in July and August and then return in September with. A webinar and a recently released report on, high-performing, commercial, rooftop, units this. Report, evaluated. The first advanced, RT you to, meet do E's high-performance, rtu challenge. October's. Webinar, will feature a chemical, free treatment, for process, water and cooling towers the, report will be released shortly and, shows very favorable, results for both for efficacy and water, and chemical, savings. November's. Webinar, will present results, from a soon-to-be-released, assessment. Of LED. Fixtures, with integrated, advanced controls. Webinars. Are always hosted on Thursdays, and we'll be announcing exact, dates shortly. All. GPG, webinars, offer continuing. Education learning. Units through the American, Institute, of Architects. Today's, webinar, is. Will. Offer one and a half units, and to, receive credit you, can complete the post webinar survey that, you should all receive, next. Time for the completion of the webinar, if. You don't receive the survey please contact Michael. Hobson. Today's. Webinar is set, to. Brought. To listen only mute mode, and. If you have, questions please submit them in the right hand side of the chat box and you, don't need to wait to the Q&A session, will which will occur at the very end of all the presentations. In fact, we encourage you to submit your questions, well in advance of the Q&A. And. With that I'd like to turn it over to Mike Lowell who will be facilitating. Today's webinar, thanks. Mike. Thank. You Andre our next slide. Welcome. Everyone and thank you attending, thank you for attending today's webinar. Here. We have the agenda, assuming. Kevin is not here first we'll have Andrea and I gave a presentation to the emerging technologies, or, an introduction to the emerging technologies, program after.
That And we'll share, the. Findings at pnnl, around. The vrf, technology. And. Then we'll have a series of GSA, people who will give us boots on the ground feedback. On the technology, as, people include David Johnson for region one in Boston, Jason. Silken from region eight in Denver. Robert. Moctezuma, from region 9 in San Francisco, and. Then Joe supered from region ten which is in Seattle, after. That we'll have, a Q&A session the course is on Draya said you can post your questions in the chat, we. Will then copy and paste those into a, Google document and we will go through those questions and address those at that time. With. That next slide. Next slide I assume, Kevin's, not here yet. So. Emerging technologies, consist, of two sub programs, we have the GSA proving ground or GPG and. Our pilot to portfolio, program. The. GPG program, is. The part of the program that basically has, an intake so every year we issue. An RFI, to the industry, people apply to the program and we select technologies, for testing and verification. Of their performance, and produce performance. Reports, on those technologies, that. Is the GPG program, the testing verification and, production. Of results, then. We have a pilot portfolio. Program and frankly. Our program, is nothing more, has accomplished, nothing if we don't then deploy, those proven technologies. Within our buildings, so. That is the function of a pilot the portfolio, program is to get those proven technologies, that we have tested and verified and. Get them into our buildings, so we can improve our performance of. The portfolio within. GSA. Next. Slide. And. I'll. Jump in here and, give. Perspective, on why why. Why we're hearing so many multiple perspectives. On VRS. So. The, first when, when Anne Wagner from PNNL will be talking about the. Technology, review on guidance, on where VR F is best suited when. Pnnl completed, their report in 2011. It, was before GSA. Had any full-scale, deployments. Of VRS. To do measurement and verification on. So, the report didn't include, that. Our standard, M&V, that we're doing at testbed locations. But. We since, that time we have GSA. Has multiple, installations, of VRS, and they. Are these. Cases. That we'll be hearing from are representing, different uses, of vrf. Kind. Of at some of those places where VR F is best suited so, at the mocha courthouse. Vr. F was chosen for, a need. For a simultaneous heating. And cooling so. When there's a challenges. With tenant, comfort, and. You, need different levels of, heating and cooling vrf was a good solution there. At the Wayne Aspinall, Federal.
Building This. Was a case where there was a. Historic. Historic building, and in. The retrofit, there's limited room for ductwork changes, and so this is another case where vrf. Can. Be a good solution. The. Bakersfield, courthouse. Installation. In 2012. Is, vrf. Is used for several separate data center spaces, and, GSA. Has a number, of installations of vrf. Used. For these separate data center spaces. And, then, the region, 10 at the Vancouver Federal Building is this is another courthouse, with the need for independent. Temperature control, so. We're, we're. Fortunate to get to hear so many kind of on-the-ground feedback, of the installation. Of how vrf, is working and also. This report, and. Guidance from pnnl and with, that I'd. Like to turn it over to Anne Wagner. Thank. You man. Thank. You. And. That's. Enough of that when we can go to the next slide. As. Andrea. Mentioned when, GPG, commissioned, Pacific, Northwest, National Laboratory, to. Evaluate, BRF technology. GSA. Did not have a vrf implementation. That was suitable for field study. Consequently. We performed, our evaluation, by examining, available, literature and talking. With industry, experts. The. Study primarily, focused, on the energy savings potential of existing, buildings I helped. With this effort and today I'll share some of the information from, the 2012. Study as well, as provide an overview of the technology. Next. Slide please. According, to 2012, CFX data about. 44%, of energy used by commercial buildings is used for space heating cooling. And ventilation. Even. Though VRS, systems, are the primary, type of heating and cooling systems, in Europe China, and Japan a small. Portion of office building in the u.s. currently, uses technology. You've. Probably heard this technology, described in several ways the. Technology, was developed in, the 1980, and designated. As variable, refrigerant, volume. Or vrv. But. The abbreviation. Or term BRV, is trademarked, so industry, generally uses VRS to describe multi split systems, that, use variable, refrigerant control. Next. Slide. This. Graphic. Example, layout of a vrf system, providing. Independent temperature, control to a variety of spaces as. You, can see in the drawing, BRF, systems, are comprised, of multiple indoor, fan coil units connected, by refrigerant, piping, to, an outdoor unit. The. Outdoor unit has at least one, variable capacity, compressor. Vrf, is an all-electric. Technology, and, there's. Three, primary, types of systems, the. First type is the, air conditioner, and this. Type of vrf, system, only, provides, cooling. The. Second, type is the, heat pump system. This. Type provides both cooling, and heating but, it can only provide heat transfer, in one direction at a time so. In other words the whole system, operates, either in the cooling mode or in the heating mode. The. Third type of vrf, system, is the most efficient, type and it's, the heat recovery, system. Okay. We've got a screen saver but that's okay. The.
System Includes controls that allow simultaneous, heating. And cooling. Simultaneous. Heating and cooling systems, afford substantial. Energy savings, and this. Picture illustrates how, the system's able to remove heat from the blue spaces that need cooling, and provided. Two distinct, spaces that require heating, when. The heat is transferred, this way the compressor, operates, less saving. Lots of energy. BRS, systems, control. With precision, the. Flow of the refrigerant, is varied to each of the indoor units to match the space requirement, and the. Outdoor, unit includes an inverted, River compressor. This. Combination of controller gives these systems, the ability to have a broad capacity. Range from as low as 10% to. 100% next. Slide please. One important aspect of VRS systems, is that they are fully, engineered, systems. All. Of the equipment including. The integrated, control system, is provided. By the manufacturer. These. Systems are modular, and have, a limited number of components. They, include as you can see the pictures from endorphine, quails outdoor. Units and a controller box. Each. Of these components, are relatively, small so, installation, is relatively easy in. Fact an outdoor, unit can be transported, to a roof and a six-person elevator. System. Designs vary among, manufacturers. Some. Brands of VRS systems with heat recovery require to refrigerate pipes, and some, use three pipes. Systems. Are designed specifically, for each application. Incorporating. Appropriate, components and control. All. Of, the components, are proprietary. Each. Manufacturer, has its own unique, components. Controls, and piping configurations. One. Manufacturer, system cannot, be integrated, within others. Also. To ensure that VF, v, RF system performed, as. Expected. All. Of the professionals, from the designers, to the operators, who are involved in the system implementation. Must, have received training from, the systems manufacturer. Next. Slide please. The. RF. Quite different from conventional systems. In several ways, here, are some key differences. The. First I'm showing I mentioned. Earlier which is a broad capacity, range of vrf systems, from ten to a hundred percent. Whereas. Conventional, systems often, can only turn down to 50 percent. Another. Significant. Difference is, that conventional, systems move heat through a building using, water or air. VRS. Systems, use refrigerant. Consequently. VRS. Systems, use little to no ductwork. However. VRS. Systems do not include outside air so. Either a completely. Separate, outside air system is needed or. An outside, air system, needs, to be integrated with the VRS system. Now. Some renovations, have taken advantage of existing ductwork, and use, it to provide outside, air to spaces, or to the indoor units. Next. Slide please. Here's. Nick, table from our study so in 2012. In our, study we, included, this table, it. Shows a rough, approximation of energy, and energy cost savings potential across a portfolio, of building in many, climate, locations, our, sources. Included, two simulation, studies as well, as other studies. Now. If you look at the bottom two rows of the chart there kind of two heavy gray you. Can see average savings from vrf systems, compared. To several types of conventional, systems. The. Second, row from the bottom says. Average energy and cost savings from vrf compared. To systems with electric, heat. The. Bottom, row, provides, the average savings comparing. VRS systems, with, gas heat. Next. Slide please. Here's another table, from our study it. Shows savings, estimated for a range of GSA, Building EU s, what. We did is we looked at the average EU, as in GSA regions, and were able to calculate the average portfolio. View, of sixty, point seven and you, can see that on the top row under. The column labeled average. We. Broke out the annual heating cooling and fan energy, use from the overall building energy use and this is shown in the next rows. Then. We used a range of utility, rates from GSA, to, estimate, the HVAC, energy, cost savings from. Using VRS, the. Estimates, were best, mates were, based on thirty four percent reduction, when, compared with the chilled water Vav, system with electric heat now.
If You look at that green highlighted, it's, 18, cents per square foot. This. Is the estimated, cost savings, for the average each, GSA. EUI using. The GSA, average, utility, cost in, 2012. Okay. Next slide please. Historic. Buildings can, be very good candidates, for VRS systems, especially, if there's limited space to install or. Change systems, a. Primary. Feature of VRS is that they are less intrusive than other systems. Refrigerant. Lines are, run instead of ductwork and these. Require only small holes and walls and ceilings, and need, minimal clearance between floors. The. Indoor units can be located, in the conditioned space or. Their units available with a low profile, for installation, above a ceiling. The. Smaller size of all the components lends to, the ease of staging. And installing, the pieces of the system while, minimizing. Disruption to, a building. Frequently. Historic, buildings, have a variety of separate, spaces that need individualized. Comfort, control. Vrf. Systems, are well suited for these applications. They. Precisely, control, the amount of refrigerant flowing, to each indoor, unit and can. Include many indoor, units of different. Cassadee's in configuration. There's. Also the bonus of providing, simultaneous. Heating, and cooling when. The system includes heat recovery. This. Allows the transfer of heat from one zone to another and. Reduces. The operation, of the outdoor unit, saving. Energy. Next. Slide please. An. Important, consideration for the selection of a system is cost-effectiveness. And these. Two charts, show number of years required for simple paybacks. The. Y-axis. On both of, the charts lists incremental, cost, the. Columns, show, various. Energy cost savings value. The. Table, on the Left compares, vrf, systems, to Vav systems that. Have hot water reheat. And constant. Air volume systems with. Gas heat. The. Table on the right compares, VRS to, Vav systems with, Electric reheat. The. Service life of a VRS system, was assumed to be 15, years. To. Self with the white background show, options, with simple Bey pack simple. Payback of, 15, years or less and the. Gray background designates. Simple paybacks of greater than 15, years. Next. Slide please. There. Are barriers in imitation. The. Complete, VRS, system must be provided by just one manufacturer. This. Requires, combining, the design with the installation, and commissioning of, a system, this. Approach conflicts. With the design-bid-build. Procurement. Approach. Currently. GSA's. Procurement. Process begins, with the design, then. The project is put out for competitive bidding. However. A proprietary. Design and, integrated, inflamation, approach for a vrf system creates. A hurdle to getting competitive bids from, other manufacturers. Systems. Another. Barriers. First cost. Initial. Cost of VRS systems are, often more than conventional, options. However. There. Are cases where cost may be similar or less this. Can occur when there's substantial space. Constraints, or challenges. To alternative, system installations, such, as installing ductwork, or, increasing, weight bearing, capacity, to a structure. Also. Incremental. Cost and lifecycle. Cost should be considered, to better compare, but, lifetime, total, cost will be a. Third. Barrier, is uncertainty, of savings, there. Are not many cases, documenting. The savings realized by VRS, systems, also. There are three types of systems, so, care must be taken when examining, savings documentation. There. Are HR. Ratings, now and, these. Provide verification of, equipment, performance at certain conditions. Next. Slide please. Where. To apply the RF. She. Says not one-size-fits-all, but. There are many opportunities to use the RF systems, some. Applications. Are stronger, candidates, than others. Merit. Severe RF systems include energy savings, ease, of installation and, degraded. Controls and comfort. Potential. Project, characteristics may include the need to upgrade the HVAC, system or, to add cooling.
Project. Space constraints, such as limited, room for ductwork minimal. Clearance or. Minimal space for equipment can. Be reasons to consider VRS. Projects. That have multiple spaces. Multiple. Separate spaces with various heating and cooling needs that, would benefit, from precise. Independent. Temperature control are. Also good candidates, for BRF. Buildings. With electric, heat are good, candidates, because, both the heat pumps, anti recovery, systems are more, efficient, than resistance, heating. If. The, building can take advantage, of the heat recovery offer best simultaneous. Heating and cooling systems, then, this type of VRS can, help you achieve your energy, reduction, goals. Our. Studies, termined that there are opportunities, for gsa, buildings to, benefit, from vrf, technology, and that. The best building, square footage range for gsa between. 5,000. And 100,000. Square feet. There. Is no quick and it search of the question, where, is the best place to, use this technology. But. As you've heard there, are a lot of things to take into account when determining if, a VRS system, is the best choice for your project. Now. I'll turn the webinar over to David Johnson and he'll present on GSA's, experience, with, the system installation, with, the Moakley, courthouse, thank. You. Thank. You and good. Morning everybody, from, Boston. Massachusetts region. One New England so, region, one installed, a VRS system, at our multi courthouse which, is our large federal courthouse in the Seaport District of Boston, Massachusetts so. A little bit about the mogli it's just, shy of a million square feet it, is a federal. Courthouse ten storeys and, this wasn't our project, that we did in valuated, in 2009, with the retro-commissioning and, we were looking at a simple payback of about six years after that Commission report, we. Had planned to do the ninth, and tenth floors of, the, core of the Moakley but. Due to installation, costs mostly driven by the need of the courts to have this work done after hours we actually, ended, up only doing a partial install, on the, tenth floor of HP 17 other 26 phases. Which. Was about half the ninth and tenth floors and we completed this project in 2011. So. For those of you who want to know a little bit more about how, that played out we completed design in April 2010.
And Were able to give the construction nervous proceeded in July of 2010. Construction. Started in March and we completed, those phases. In. The course of several, months so. It. Was a. Was. A detailed project but. It would have been about the VRS system next slide please. Yeah. We did use end up using a water-cooled, instead of air-cooled system there at the Moakley the, reason we selected that was there are few key security concerns, from the Marshalls and the courts. Most of the roof openings that we would have had it, was a little bit easier for O&M to access the equipment and, provide that corrosion. Due to marine, conditions if you saw the photo there the Moakley, courthouse is, on, a pier out into Boston Harbor so, and. Then when we looked at the finances, and the payback the it, had a slightly better payback to do that so. We ended up using existing, cooling, towers and an. Existing, heating. Plant to give both. Heat, rejection and to give the system heat. It. Also allowed us to use a refrigerant. Pressure differential, on the high-low at the coin units for leak detection rather. Than the occupied space least attetion required, by ASHRAE 15 a. Little. Bit on, the maintenance side cuz looking at operational, excellence and we would play some washable filters with mermaid filters, and our boxes, there came with a whiner. For sound. Next. Slide please. So. How, did we know, we. Installed it in the. Installation, like I said was after-hours, and, we would return the spaces, to occupancy during the day which. For those you who work with courts know that that is a tricky. Process but it was a very very. Successful for us but. How does it hasn't worked out since we installed it back in 2011, well, like. Many of you in the field no news is good news and, we do not hear a lot about the BRFSS about the multi which is for, us a great success, when. We look at the system we see that we've had a 12% reduction in overall utility, spend to. Be upfront about that that, does include other upgrades such as bas, and lighting and since this, did not have the type of spoken. About earlier we didn't do full mnd on this as it was a our, upgraded. Not so much a straight-up, GPG. Projects like some of the other ones a portion. Of that is for the BRS system. But. When we came no news is good news we mean both from the building operators being the GSA property management staff and our, O&M, contractor there, but also the tenants have no complaints, as well, so that is always a good thing it's, spoken to and I see some of the questions in chat yes, it we did find that using the proprietary controls. That come packaged. With the unit is, actually very, good for the install. But. We. Do have supervisory. Of. That, linked into our bas, so, there is a question about do, you have package controls on your killer system at our package - the chiller system but then talk back to your bas and your BS monitors, that system and that is exactly what we use there at the Moakley. We. Did as far as how robust was to install we, did have a unit go down, but. That unit was replaced by mr. B she they were very responsive, to our issues so we do know that there is some feedback from, across the nation that some will get into later about how, widespread. Is support for this and how do these systems get supported because they're relatively new to the US market. But. We have had good results with the manufacturer, being responsive, to any issues that we do have with the system. Next. Slide please. So. As, far as lessons learned yeah. Using that unit that manufacturers. Control interface was the lessons learned the, BS does only have control of monitoring of that system, of that subsystem. And. Performing, that site verification during, design to make sure the sufficient, physical, space for those units was also an important, lesson learned a. Few, other things that we did, to. Make that really work out is that we did set in the OEM to, a multiple. Day off-site. It. We found it was important because our, O&M contractor was, not familiar with how the. RF system would work and how to maintain it so it, was for us it made good, sense to go ahead and, spend, that money and we actually got six of the contractors. O&M staff, through. Training and I think that that was a good lessons learned in something that we would like to replicate in, other and further projects. Next. Slide please. And. Really to conclude is that they. Have, an obvious energy, efficiency, and, we do use them for simultaneous heating, and cooling not to miss that point courthouse. Because of the type of lot of affinity it is it, actually has the need to heat one space while cooling another so we're able to use that inherent, simultaneous, heating and cooling situation.
That Vrf gives us to, drop our energy call at the same time it actually makes the cousins more comfortable for our tenants so there's good payoff there our. Units, are very quiet they have a quiet operation, and. It's actually fairly low maintenance. They really just change the filters and clean the coils on them. For. Safety in the courthouse we're not research leaking air from one zone to another which. There are some concerns about in a courthouse for airborne contaminants, and allergens and the. Flexibility, that we gained especially, the a flexibility, during this install was able to go zone the zone and, you in stone well the rest of our building remained in operations, it. Was really quite a sight to see and, there. We have quite a bit of photos that we could share at another time of how we how, we did that and we would return a space to full operation, for a client, like the US Attorney's Office, or. The US Marshals during, an, overnight and. They had full operation, and space during the day so. That is that is a very. Positive for us. So. Would we do it again if you always the other question and the question the answer that is yes we're doing additional, BRF installations, right now that. We probably will talk about it but they're in a further. Presentation. But we got one going into the border station right now so that's what we do, what. I'd like to do is that. Concludes, some oakley's presentation. From. Region 1 but, I like to turn this over to Jason. Token. And Roger Cheng from region 8 because they're gonna talk about another courthouse, that they've, done out there so, Jason in marketing, before. Roger. Before you get started, I'm here hearing some feedback, from a line, and I'm not able to mute it it's an area code four one nine, four. One nine and a ten five zero eight zero so we're hearing feedback from your phone if you could mute your line thank you and thank. You Jason and Roger now. Great. Well thank you, so. I'm Jason silken I'm a architect. And project manager, from GSA, and region eight and I'm here with Roger Chang I. Am. Right in China I was an engineering, leader on this project, with the other group so. Next. One. So. To provide. A little bit of context, to this install. The. Wayne Aspinall federal, building and you guys courthouse, that located, in Grand Junction Colorado, the. Injunction the smaller community, on the western slope of the, state and it's in a relatively. Dry and arid climate, the, building itself was constructed, in 1918. It's, on the National Register, of Historic Places, it's. A small building a little over 41,000. Square, feet, three. Storeys above grade, however. It houses nine, federal, agencies, including, a fully, functioning, District, Courthouse, the. Modernization, of here. Was funded, by the Recovery Act we. Awarded this as a design-build, contract in. 2010. To Rogers team. Construction, was completed in 2013, and in September. Of 2014. We completed about, an 18-month, performance. Verification, and M&V period. To. Dial all of the building systems in the. Building, or the project scope was a top-to-bottom. Modernization. Of the building we, are replacing, all of the major systems, in. The, building all of our many of which we're failing at the time on. The flip side we are also we stacking, the building to kind of create a more efficient, way of improving our, RSF. But in addition that. Allowed us to preserve, and restore significant. Aspects, of the building's interior, that had been lost through previous renovations. And you can kind of see that on those, two. Photos to the left the pre, project. Conditions. This. Kind of overall. Approach. To this building or skill. For this project rather, gave, us an opportunity to, really kind of approach this of the whole building design. And. Since this was in our project, the end product was required to be a high-performing, building and since. It was a historic, structure of the modernization really, needed to support. For large preservation. Efforts, and so ad awards, are performance. Goals on the design-build, contract, really. Kind of evolved beyond that our minimum performance criteria. But included. Stretch, goals such as LEED, Platinum and, net zero energy for, this project. The, means ideal this backstory is important is all, of these factors kind of created the metrics, Roger and his team used for. System consideration, on this project next, slide. So. Working with our, construction, manager, Jacobs, at, the RFP, stage for the design-build, contract. They. Created a performance Beck which offered up systems, for consideration, kind, of beginning with a baseline followed. By. Improvements. To the baseline that we felt could better, meet our overall, goals to, this project and so that really. Kind of created. Six. Metrics. That we were looking for in terms of system consideration.
Footprints. Exact. Related, to our preservation goals, we wanted something that was slim and could allow us to. We. Re-establish. Those original, volumes, in, the building's interior. Efficiency. For our energy and sustainability, goals. Zoning. Considering. The number of agencies we have in the building as well as their orientation. On the floor plate zoning. Was a major consideration, on this IQ. Both. Ferrara, and lead, response. Time we, had agencies, like the u.s. district courts and the IRS who see a large influx of visitors in, a very short period and. Lastly complexity. We. Needed a system which could be managed, by. The OEM in the building and also be able to be maintained, locally, knowing where, Grand. Junction sat between the, closest, major city which, was about three to four hundred miles away so. I'll turn it over to Roger to talk about how his team sort of evaluated, these systems. Well. Thank you Jason thanks. Everyone for allowing. Us to be on this, webinar. So. We used, energy modeling to look, at the variety of systems that Jason showed on the screen even from, the you award faith we're, looking, at what provide best value to GSA, to select, the. Radiant cooling and heating system actually was. Came. In a close second, to the system, the, DRF system, had. The best, overall lifecycle cost out of all the systems considered. But. Really one. Of the biggest, drivers is just its ability. To be fit within, this historic building from, the early 1900s, the. Variety. Of things that, are available with a VRS system, provides. Significant, zoning flexibility. A good acoustic, footprint, and, also addressed this desire, to have very. Short, warm, up or cool down times due to the variety of schedules used by the different, tenant. Agencies in the building, we. Ended up choosing a water source BRF. System, this, was a measure in, order to drive the energy use intensity target. Achievable. Down further in, order to balance with, the limitations, to how much on-site, renewable energy, could be provided. For, the Netzer energy goal of this project we. Ended up with six twin sets of water, source condensing, units you can see these installed on the left side of the picture on. The screen and each set had between 12 to 20 tons of nominal capacity on. The indoor fan coil unit side we, primarily used, a ducted, low, profile, showing mounted, units, these. Were. Installed. With the relatively, short amounts, of supplied ductwork, and provided, with ventilation air, from a separate rooftop, mounted dedicate. Outside air system, that. Dedicate outside air system, did, have additional. Zone, level control with. Vav. Single. Duct boxes, in, the quantities that you see on the screen Virgin. Piping, was braze copper, in a two pipe configuration. With. 10 branch controllers, each was 8 to 16 notes next. Slide. So. Just some general. Initial, observations. As has been mentioned, for. Every manufacturer. We, are dealing with very proprietary technology. So we, are operating, these, in somewhat, of a black box condition, so. Unlike, a traditional airside or hydraulic system where you can measure temperatures, and flows and. Do an energy balance to see how it's performing in relation, to, electricity. Or natural gas input, there's, actually much more difficult to do with the VRS system and so, one of the things. That we were challenged with during the mov period, of this project is to say, do. The results actually match the mod results, and. If there is a deviation is, it because of the way the system is installed or is it because of operating, conditions or, is it because of someone to teach the modeling software so. There's one thing that we had to consider in. The post occupancy stage. Although. Variable, is in, the title of variable original flaw as a system the, operation, is not a continuously. Variable, modulation, but, rather is actually in steps the. Water source heat pumps we use each, have 12. Steps of control. As, has. Been mentioned controls, integration, can be challenging, especially if, you want to do some integration with a building, automation system, through, open protocol, in. This particular case our biggest challenge is actually doing, sub-point scheduling, for. Each tenant agency, by time, of year and. Also linked to outdoor conditions, eventually. We were able to. Integrate. To, the needs that we wanted but, it did take what some time in order to particularly, have set point limitations, so for example during cooling being. Between 75, to 78 for, heating between 69, 72, initially. We had to have a wider, range in. First. Installation. The. System really is optimized, for standalone. Control, so when these are installed we're just using the wall-mounted thermostats, and maybe a may effect provided. Touchscreen. Panel they, work very well and, they tend to be fairly, easy to Commission it is again when you're using that building automation system, that doing everything.
You Want it to do, can be challenging, just, the data on the right is just our energies intensity, for the building we originally had a target of around 15 for Energy's intensity. After. Observing actual, process, energy use from the different agencies this. Was adjusted, up to approximately, 20 in. The building in its first year after, some. Systems optimization. Operated, close, to that target and. After. Considering, the contribution, of renewable energy operated, close to 6 for a DUI so, significantly. Less than a median, courthouse. Office building for this climate zone next. Slide. One. Thing we found is that there is really no benefit, to twinning, in this particular application, for a water source application. Unlike. A system, that might have two compressors in this, type of condition. With, this manufacturer, one compressor, failed actually. The entire unit goes down one. Other thing we observed as a HRI, rating, process a while it does allow for comparison from, one system to another between. Different manufacturers, it. Doesn't have a rating, condition, below 25% as, a testing, point. This, particular building, had a lot of conditions. Of operation, where we're under very low demand where. This system doesn't necessarily, perform as efficiently, overall, performance efficiently, but, it may not turn down as. Well as one might anticipate. Our. Sizing, in. Retrospect. Was more conservative that, needed in terms, of applying, some, of the GSA standard, guidelines for a process load this. Building ended up being a heavily, process of managed building operating, down as low as 0.1, watts, per square foot a. Night. In about 0.2, during a day and. So there. Was the ability to potentially. Apply more diversity, in the design sizing, as, a been mentioned energy modeling, they're. Not very made tools that can natively model, these systems, nd, ratings do, need to be taken to account for actual, install pipeline the, fittings, the altitude, of the installation, and also, defrost, will return cycles, second temporal interrupts performance. The. Graph that you see on the right is actually annual, electric demand for the building pre. Modernization. Just install lighting power density for, this building, was 2 watts per square foot post, renovation the whole building was able to operate under, 2 watts per square foot with, the VRS system, considering. Approximately, 35%, to, the energy use of the building overall with. A one-hour electric, peak of approximately, 1.2 watts per square foot so a very very efficient. System, next. Slide and. Roger, we're getting some feedback that it's a little hard to hear you so if you want to. Pick. Up or move your microphone, that would be helpful oh sure. So. Just some considerations, for future use we did end up using a two pipe system on this project, while three pipe is common, to most. Other vendors, other than Mitsubishi, and, there, is potentially, higher efficiency.
Potential When you are really utilizing, the heat recovery application, for these systems with. A three pipe configuration. One. Thing we did realize. On this project that's very interesting in working with the manufacturer is that, because there is still a separate, condenser. Water loop in this particular case it was tied to a ground source heat exchanger. In. A parking lot adjacent, to, the building that. Is a component, that is not directly controlled, by the vrf. Control. System in that case is controlled by the building automation system, so, there's a potential for some. Integration, challenges with, how those to react. To each other while, when using an air source system all of the controls are completely packaged, to integrate together and optimized, by, the particular, vendor, so. In this particular case we were trying to do full variable, condenser, water flow and actually, found that the manufacturer, had a limitation, actually an error in their documentation, about what was possible and for, this project they ended up making, revisions to future, product lines based, on some of the. Observations. From this project, fail, or change whether. With a VRS system or any sort of fan coil unit or fan powered system. Is a consideration, in this project, we had over 60 distributed, fan coil units so, we used care to make sure we address how, those filters are changed but there is so that decentralized. Component, that needs to be taken, into account water. Source systems we believe even in, one, more generation passed what we use for this project can, actually perform with. Better variable, condenser water flow it. Is a very complex refrigeration. Cycle, that, requires that that controls packages, provided can. React to that complication. Of complexity. Next, slide. And. Just, the last slide here it, was important, to plan, commissioning. At env as early as possible in this process, to. Understand, how the data that's collected will, be used to further optimize, performance. One. Thing we observed for this project not only with this equipment, type but other equipment. On the project this, is that equipment standby, energy performance is not always available, but. For a ultra low energy high performance, energy building, target, every. Bit counts and. Sometimes, even, just parasitic, control. Panel energy can. Really add up for this system we found a, continuous, 300, watt, control. Power. Demand, that. Adds up for a building that's trying to target a 15-4. Energy's intensity, as we, saw there were some challenges with controllers. Integration, for sub point control we. Had to tighten that several, months after occupancy. And some, tenants were. Initially. Taken, off guard when, they could have a wider range and it was narrow later on so it's important, to get. Players from the manufacturer, in the control center in as, early as possible so, that could be setup as, early as possible. This. Last image, on the bottom just has, an electric demand profile, for, one of the twin sets. Then. You can see some, of the modulation, that occurs over a 24-hour, period the, blue versus yellow, red, shows. Compressor. A versus B cycling. In. Flip-flopping. So. Thank you for your attention. Questions. On this particular. I'm pleased next. To introduce, Robert mother, Zuma who will talk about a, project, in Regency, fine. Good. Morning everybody my name is Robert Watson Emma from region 9 on building. Management specialist in the central California field, office the, biggest field federal courthouse is, part of our inventory in. Vegas. On. The next slide please so. The, biggest field courthouse was constructed, in 2011. It's a relatively small building, as, far as our inventory goes in. Art used. For BRF it's used only for for, dedicated. Server, and equipment rooms dispersed. Throughout the building, totaling, only about 400, square feet in total. Has. A master enslaved air cooled heat.
Pump Outdoor units on the roof and four. Terminal boxes. Dispersed. Throughout the building if the two pipe system. Design and it's only used for cooling and is. Operational, 24/7. The. Remaining space is conditioned by an air cooled chiller in, combination, with an, active beam system, and only, one, air. Handling unit for the rest of the building the. Next slide please. So. The. Benefits of the bakersfield BRF insulation have been. Due. To the dish first location, of the server room slash equipment rooms that it serves throughout the building some, on the first floor someone at second floor it. Would be. The. Runs. Were for. Fighting. For a traditional, system would be. Not. Not a possibility, in this location one. One. Outdoor unit serves four different agencies the US Marshals Service. Coupled. To bankruptcy and trustees. Server. Room, security. Equipment rooms. Some. Level of redundancy, we. Experience, and knowledge of the slave unit but due, to the fact that these. Units. Are twin together. The, master was able to continue running obviously at a reduced cooling, capacity, but we, were able to maintain. Continuous. Operations. For our tenants and, we more. Efficient than a standard system due to the height turndown. Capability. Of 20, to 100 percent, on. The next slide please. And. We have had that make some repairs to the system. We, experienced, as others. Have mentioned that a little bit of a black box. Situation. Limited. Access to troubleshooting, and repair information for non factory. Certified, personnel. Along. With that I know, that folks. That were originally part, of the project the operations, and maintenance team, you, know we we, do periodically. Have. Turnover in our operations, and maintenance contractors. So training of those contractors, and the. Following. Contractors. You know when operations, the maintenance contractor, changes, it's, definitely a consideration. Now. Weaknesses, in the system has been, electronic. In nature so, again we kind of get into the black box area, where it's not. Traditional. You. Know refrigerant, and electromechanical. Components, that we're experiencing, trouble with in, that sense the units have been very. Reliable and relatively, trouble-free, the experiences, that we've had is been involved in like. Serial, communications. Between the master and the slave unit, and it really drives us into a corner where we are almost. Forced to rely on the manufacturer. To. Provide us that. Technical. Support. Again. Limited vs integration. The. Manufacturer, in this case is Dakin they, do have a back. Net interface, that, does allow us to. See you. Know temperature, setpoint operational. Status and. Whatnot so it's not uh, it's. Not completely standalone that sense next. Slide please. Okay. So with that I'll turn it over to Jose, Eber to ten. Come. On Oh super. Reason. Ken I was, a mechanical, engineer reviewing. These design drawings and then actually going down to. Do. A quick commissioning. Of this installation, because. We we didn't have commissioning at all, next, slide please please. So. Some. Of the issues that I've seen with, this installation and, others prior, to joining the agency. We. Talked about the limited visibility, into the BAS and black box that. Both Robert, and Roger. Had talked about in depth so, I won't go into it it, makes it tricky when you try to do any sort of commissioning of course, trying. To see what's into the system really, just have a you're. Giving a set point and maybe, you're having an alarm coming back but, other than that you. Can't really interrogate the system very much. Condensate. With, these systems so they're they're either the reader gravity, or their pumps from, the unit itself from the cassette I've. Seen both this, insulation was a was. A pump installation so, you have alarms associated, with the pump within, the cassette unit. But. Then it's. Been going to be pumped in, the insulation. They pumped it to another booster. Pump if you will condensate, booster pump which. Is not on the CMS so, we didn't know whether we, had a failure of that booster. Pump for the condensate, and it overflowed, and nor courtroom area because, we didn't know it, was an issue so. So. There's issues with condensate, you have to insulate it if it's they're, going to have human conditions. So. That there's just concerns, associated with the condensate, that it's done correctly. And.
If It's gravity if it's gravity, and there's no pump acting, units we've got to make sure of individually, trap those units so, that they can drain properly, so. That's condensate, refrigerant. We. Got to make sure we're compliant with ash for a 1534. In terms the amount of refrigerant we have in the space that's, up to the designer to make sure they adhere, to but. It's also up, to the contractor, to make sure they put the proper refrigerant, in we. Got to make sure we properly, insulate those lines because again we're gonna sweat above the ceiling we've, got some pictures of that not working with, - and. I think others have talked about the training and we've got another installation, and Anchorage where they're we they don't know how to operate it so. That's. Key data XY. Please. So. So here's some examples. Of poor, refrigerant. Installation. So, that vapor barrier than isn't. Sealed so you know you have an opportunity to sweat it, was just not done well so. On the right is the cadet unit itself on. The Left I believe is the the branch controller. So. Lots, of opportunities, for persuading. Above above, the space and if you look at it they actually use the flexible. Refrigerant. Line, which. Really it could be like spaghetti going through the space was. A little concerning that wasn't a nice they weren't nice clean lines, so. There was opportunity, for us to it. Was good for installation. Easy. Installation but, in terms of trying, to make sure we know where those lines are we don't hit them in the future that's, a bit of a concern next. Slide please. So. We talked about the the condensate, so. One. Thing that I've seen in several locations is the use of PVC on the common sake so. On the left hand side it's a poorly supported BBC. Which. Then they would replace with the copper on the right hand side so, notice. What, on the right hand side this is the booster pump so. The it's, going to be pumped into this. Reservoir. For, the booster and, it's not sealed you can see there's a little annulus there so when it overflows, it's just going to flow right out and spill into the court room which, it did and. That little booster pump wasn't on the VMS it's, still not so, the. Lack of communication. In terms of what. We should be doing to, properly. Monitor our system next, slide please. So. The actual Vancouver installation, itself services. In Portland Oregon so it's a mild climate as, all other questions. But. It does have many plus degree days, for. For for. Several days during the summer so it does have look cooling load and. That's really important, with. Echo, what Anna said earlier. This. Is a small installation, but, in order to get simultaneous, heating and cooling, in. My thing you need to look at a whole floor installation, or whole building insulation that. You get the opportunity, this. We did not so it's only five thousand square foot out of the twenty thousand twenty some about, twenty percent of the building on the second floor two-story building it's. Got the, occupancy is is. Courts. Bankruptcy. So there's some courtrooms and then. There's other spaces so IRS, and what. Was happening here is we were freezing, out the IRS because we, were trying to make it colder for. The courtrooms so. They just wanted another system, and that's what this was so, that they had independent control in the courtrooms so, I think it's a three zone system. Pre straightforward.
Really. No opportunity, for simultaneous, heating, and cooling it. Just, it's meeting a need so. Next. Slide please. Of. Course additional, ductwork I wasn't, needed in one of the main benefits with. The exception of the outside air and, on this system incidentally. So. If. You're not doing the whole whole. Building you don't have enough a real good opportunity for a dedicated, Gillett system so, you can't, minimize your kind of chasing through the roof this. System used to last May the e RVs, so, you had multiple penetration, surgeries, which. Really made the system, quite complicated. So. We, didn't see an efficiency improvement, on this building the tenants aren't happy though I mean they're happy. With the system because, they got a standalone. System just for the court room so they were going to be happy whether we went with Vav or any system I. Mean. We're not over cooling the. Other floors that were, on this it's. Quiet, although. We did do a sound test and the sound test showed that it was going to be loud louder. Than what the US courts, would allow, but. They haven't, complained yet so. And. Part of that could be you, know there's a low medium high setting, on these cassettes so. You're. Cycling through those those. Settings, so as. An, occupant sitting in the space you're listening to this cycle, and you may not it may not be loud but, it's just it's different not something you're used to hearing. Mostly. Used for cooling yeah, because, you've got a high occupancy load, for the courts, next. Slide please. So. The BAS. Automated. Logic. Screenshot. So. You know you've got all kinds of. Feedback. Within the system. I we've. Limited size tied into the BAS, let. Me control we talked about that, next. Slide please. So lessons learned. The. Exhaustion, the intake, so. We've. Got a few 100 permits that says you've, got to have a separation. Between the exhaust and the intake, so. When I walked up there they, didn't have this on the drawings insistently, ever would have pointed it out early on so. There's like three or four feet separation, between those two, it's. A lot a it's, not a dedicated, OS system if it were for the whole building we'd have a better opportunity to provide that separation, but. Instead we've got these two little independents and controls and, incidentally, there are two penetrations, here exhaust. Alpha air and then, for the other last name there's. Another, exhaust, and, outside air so it's four penetrations. For, just this little 5,000, square foot area so, in terms of your penetrations, through the roof and mitigating, water damage and future this, is not the, best solution but. They weren't far, enough apart we, had a debate as far as whether they, needed any separation, at all if. You look in the day lads ASHRAE book you, know it talks about a minimum of 10 feet, which is which, is the mechanical, code requirement, they. Argued it wasn't an exhaust but I. Don't. Agree with that so. Yeah. So we talked about the condensate drains. One. Of the issues we had in the building was, because we were able to disconnect the old system they didn't properly, disconnect. It completely, they just used the OB DS. An, Arab led by and you could hear it so you got actually capped up or, next. Slide please. Oh, okay. So um vrf. Recommendations, so, new, VRS design guide is one thing I'm going to throw out so. I can turn to my ASHRAE. Systems. Equipment. Book, chapter, 18 and you've. Got some guidance in the ASHRAE handbooks. But. There is no book. That I can pull off the shelf that provides you the design guidance or install, guidance. You know for example there's a nice last ASHRAE, book that folks, can reference there's. A nice chilled beam reference. Guide and. There's a reference, for the SAT so there's lots of guys out there that ashtray has produced that, technical. Folks. Have produced but, there's limited information about the RF systems. And. I think that's something, that the industry is having, a problem with so, we got to make sure that we get the right, contractors. That have installed this before the right designers that have, designed. This before that. Is not what we got from this project. Absolute. Records, sure. Make, maintaining adults as we support. Understanding. The limitations. So. My my experience is I've done some previous ones, with. With Camp Lejeune there, are other examples where, people have, been using VRS, longer than we have but. Maybe we want to reach out to and see what some, of the issues are and, I wanted to stress the.
Use Of simultaneity, and cooling. Weeks. We, have it on application. But, we don't really have enough various, zones that. We can use it so it was it, was kind of a missed opportunity, some, things that we still have outstanding there's. Some skinning issues associated with the IT equipment we're still not over that. So. That that's a concern you have to go into it making sure your your, folks are involved I would. Always recommend commissioning. So, that we're properly commissioning, this at the end of the system, and. There. Are some cold weather concerns, that, if you're going to use this in the cold that. You get low ambient kits, and your hike, your your, you can adjust high enough of the roof so you've, got to make sure that you're properly doing it also, with the dough add system, if you don't have a dedicated OS, and you're just using a last. Name, there are filtration, issues they can only do a Merv 7 or an 8 so. You won't give your nerve 13, that you're gonna need for. You, know this for. This courtroom type building so that's. What I have and I'm going to turn it over and, meet myself. You. Fish. -, you hear me. We can hear you now thanks Mike okay welcome. Everyone thank you. Just. An FYI we, received so many questions, when I'm going to be addressed be able to address all of the questions for the Q&A session so we're. Going to be focusing, upon those questions, that appear to be kind of more global, for the presentation. So. With that let me get started. Jim, asked are there any BRS, systems coming to the market which do not have proprietary controls. Colonel. Of the USC which, is applicable to all DoD, projects, requires. That VRS systems have open source control, compatible. With LAN works or BACnet I. Don't. Know if some. And/or, anyone knows the answer to that question. This. Is Joe I mean they may be compatible. With other systems but it's not like we're gonna be able to plug-and-play you, know, an LG, unit with a Mitsubishi unit, they're still gonna you're still gonna have to stay within that. That. Manufacturers, framework. Okay. Thanks. Dad. Asked what is done to deal with the potential release of refrigerant, within an occupied. Space how. Does one deal with the required venting, of that material and. You. I thought on that. So. This is show if you're. Going to design it for at 15, and 30 for asteroid compliance, which, just says the the size of the room and the amount of refrigerant if. You have a leak you don't necessarily have a detector, that says you have a leak and. You, don't necessarily ventilate. Them, that's not how those systems are designed like that. Okay, thank you and. Demetrius, asks how do you deal with the Buy America Act other enough, systems within the US but.
Within Our trading partners we're having issues of getting them a free from the army. So. This is Jo we did a waiver and intruder, you, have to do a specific waiver because there is no one that meets the u.s., Circle. You. So Winston, ask how is the refrigerant, line condensation. Controlled, above the unconditioned, ceiling grid I'm Joe I know you had you know as a, insulation. But. Any. Other thoughts on that. But. So, making sure that we have we have insulation to start with and then it's continuous. So, we have a continuous vapor barrier, so. If anything is going to sweat that's going to sweat certainly. Before the condensate, lines. That. But, as I showed in my photos it's. Not completely. Sealed if, if, you've, got a contractor, that's not checking. Things so, it's certainly an opportunity that we need to look at from, our perspective, to make sure quality, control, and quality insurance has been. Thanks, and then Jack asked and. That's, why and this is the question for you I understand. That Mike Rosenberg there, at P and L has done some research and shows that in the northwest climate the. Heat recovery function of the RF is seldom cost-effective. Or. Even, used much do, you have anything that you could add to that and respond to that. Sorry. As I'm you I'm not really conversing on what Mike's done but. I do know in the Pacific Northwest there, have been quite a few systems installed, I'm, in Portland area and of quite. A few that have been installed. Completely. Engineered. Designed. Including. Coupling. With DOAs systems, and other high performance equipment, that. Have been very efficient, there are. Some, cases exactly new, buildings instituted, went on the Mercy Corps that, have been found to be very, effective, again. As. I said earlier one size doesn't fit all depends. On if you do have the opportunity, to have, simultaneous. Heating and cooling a lot of buildings here don't, we. Have a lot of buildings that use outside. Air, for cooling so. We have very they, have low levels of hours. Of operation, of compressor, our systems, we, also have, facilities. Facilities. That don't have much of a heating load and, if. You, have electric. Resistance heat. BPA. Has done quite a bit of studying. On the systems, and have found them to be very successful in, a lot of their territory, when, the only heat available is electricity, electric, resistance so, they've replaced selective, resistance. Systems, with, the, BRF whether. They're the heat pump or that, heat recovery, that, are. Even more efficient, so, it again, depends, on the application, it, doesn't fit everything but. The, benefits, of the partial. Load being able to turn, down the system to very low loads, beneficial. Can be very beneficial for certain, applications, as well, as the ability to recover heat, with.
The Heat recovery, system and and, find greater, savings so. As with, many parts of the country different. Buildings. Different needs in the Pacific Northwest we, have some excellent. Applications. And some actual case studies available, and then. There's some locations. That would not be or some applications, that would not be the best so. As. I said not somewhere exactly, but Mike's been, looking at and now, I'm going to check into that since she is one of my colleagues thank, you jack. Thanks. Sam. So there any refrigerant, leak sensors and assistance that we describe do I know that show said you didn't have any but or. Any of the other presentation. Teams aware of leak. Detection, systems, and your installations. Not. On the Aspen all project, either now. Okay. I'm going to take silences, no, Jack. Asks, it. Seems like smaller, VRS. Systems are more efficient than larger, VRS, systems, what. Do you think about using perhaps multiple. Smaller VRS, systems to serve a single, larger building. This. Is Joe that's that's how they're designed so, they have multiple outdoor. Units, and they in a stage, up from that so, it's, not a really, large outdoor unit, several. Smaller units, so on this little project that we did for five thousand fourteen we just had one outdoor unit but, on larger projects that you're going to have multiples, of those, and those are added on as needed, as needed, for the load. Okay thanks and. Then, Jim asks in climate where heat recovery, function is seldom used, with. Non BRF heat, pumps be a better option and Roger typed, in yes. There's less refrigerant piping, complexity, and equipment cost if heat pump only systems, are used. Yeah. And I just want to add more that maybe relates to this as well as the previous question, what's. Really key for these systems is just to understand, the load profile of all the zones that are attached. To a single condensing, unit so, you want to exercise. The, full range of potential. With, that condensing, in it and if you have this more of a fixed load you may not really need to use vrf technology, you might use some, other just. Single. Condensing, it to a space type. Of arrangement, it's. Definitely dependent, on the each. Individual, scenario, I definitely understand the low profile, will, help drive some of the actual, design. Okay. Thanks. Roger and. Then, mark asks. And. It's, assumption can. You provide the OEM cost increase, for maintaining and repairing a large number of vrf units, located. And difficult, to access locations. Above, ceilings versus a small number a, traditional. Air handler units located in easily accessible, mechanical, rooms so I guess the question is is did. Any of you see an increase in cost and was it for those reasons you know lack of accessibility. Etc. Right. Or do you face that issue. On the ethanol project, I don't. Believe that was an issue post. Post. Construction I think. Just kind of going back and making sure your building is the right fit for this type of application the, ethanol project, is a smaller, building, under 50,000, square feet and so the. That. Kind of maintenance and filter change on those units, was, relatively.
Manageable For. For, the LNM fair I could see how that could be problematic on much larger facilities. Okay. Thanks, and. Then John asked you. Did the D rating for piping and altitude. In the energy model question mark are you, talking about pipe losses from the refrigerant, flow, what. Program did you use to model that so this would be I think specific, of the Aspen or. Roger. Says. Of Cory head Roger oh is. This gonna say so, manufacturers, when they actually, give you a submit all for, the particular, configuration. Of, outdoor unit and family, you know they, do account, for the refrigerant, piping length in actual. Peak. Energy. Consumption, heating and cooling they'll, also do that D rating for the design ambient, conditions. That, data can then be used in, maybe a wider variety of energy, modeling, tools whether it's an e quest or Energy, Pro or train tres which are commonly used right. Now to, my knowledge Energy. Plus as a simulation engine, is the only. Engine. That can natively model, refrigerant. Piping lengths impactive. Sittings impact, of installation, elevation. Kind. Of more, of secondary. Or tertiary factors. In, impacting. Efficiency, while. Most of the time the industry is using. More. Aggregate, information and, empirical, models to do the, modeling energy, plus if you know how to use that module you can get, a more precise. Simulation. But, right now there. Are still some approximations, that occur. Thank You Roger, Thomas, s, got. A number of outdoor vrf. Control board unit failures, should any. Special, consideration, be. Added. For this, these. Vrf, institutions, given those failures, I. Guess. It's all, dependability is the question. Any. Thoughts on that. This. Is Roger this may just be, looking at who has the best service presence in a particular region where a building is located and. I think if you, looked at market share for the different manufacturers I don't want to talk about any particular manufacturer. Biasing there's two there. Are a bit larger in. The United States right now than, than the rest, I've heard that there's been I think overall better experiences, with those those two big big, companies. Roger. This is Joe can we ask you in your opinion as you are. Sure. I'm Mitsubishi, and Aiken. Thank. You. Mike. Roger and then David asked have any of these installations utilized. In ground loops the. Supplement, heating and cooling and Roger. If you could talk about the aspinall, installation. Sure. So for that particular project we did have a 32, well ground. Source heat exchanger. So. Instead, of having a cooling. Tower and boiler at the condition that condenser, water loop it's really the the ground that's acting. As a thermal flywheel, in this particular project we did have a fluid cooler, just. Allow, for a load balanc
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