GPG Outbrief 15: High-Performing Commercial RTUs
Logistics. Today's. Webinar, is. Based. On a full report by, the Pacific, Northwest, National Laboratory, and, you, can find the full report as well as a one-page, infographic. And four-page report, summary, gsa.gov. Slash, GPG. After. Today's webinar the recording, as well as the presentation, slides will also be available at gsa.gov slash, GPG under, out we've webinars you, can also find a schedule for upcoming, webinars as well as a link, to subscribe to our g PG mailing list if you haven't been getting any of the webinar announcements. Today's. Webinar, is one in a series and, our next webinar will be on October 11th. And as, soon-to-be-released evaluation. On small, circulator, pumps, with automated, control, these. Small circulator, pumps, less, than two and a half horsepower are, numerous. And US commercial buildings, it's, estimated that there are more than 30 million of them but, they've typically, been overlooked. For efficiency. Upgrades, because. It can be expensive, to switch these small pumps to variable speed drives this. New technology. Provides the, variable speed capability. At, a lower cost and with estimated, savings greater, than 50 percent we. Hope you'll be able to join us on next month's webinar. Today's. Webinar, and all GPG, webinars, offer continuing, education learning. Units through the American, Institute, of Architects, to. Receive, credit please complete the post webinar survey, which. You should receive shortly, after today's webinar though. We looks. Like we're having some issues with the, email. Delivery, from our webinar, program so it may that, survey. May be delayed, but. If you don't receive, the survey within the next hour or so please, reach out to Michael Hopson. During. Today's, our. Participants. Are set to listen only but, you can submit questions by using the chat box on, the lower right of your screen, and. You don't need to wait until the Q&A session, to submit questions in fact we encourage you to submit them well in advance of the Q&A. So. Thank you again for joining us and I'll turn it over now to Mike, Lowell who'll be facilitating. Today's webinar. Thank. You Andrea next slide, please. Welcome. Everyone to today's webinar and thank you for coming, first, we'll start off with an introduction to GSA's, emerging, building technologies, program by Kevin Powell our. Director, and next, we'll follow up with the actual presentation on the report from strand Abbas from, Pacific, Northwest National Laboratory. And. Then we'll get some on-the-ground feedback, from, Frank. Campania and Stuart lankan of region 7 where this technology. Was installed and tested and finally. As Andrea said you'll follow, up with the QA and that. Will be the end of our presentation. Next. Slide. And. With. That I'm going to turn it over to Kevin Powell. Kevin. You might be on mute. And. Kevin. You still on you Oh. That'll. Can you hear me now yes. Okay, I think, I was needed there sorry, okay. So next slide please. This. Is everybody now will know what I look like good thank you so just, a couple of quick notes about our program, our. Program was stood. Up about. Seven. Years ago at this point the, idea is to provide a, one-stop. Shop a. Central, point in GSA. To. Look at technologies. That are essentially. The best, of what. Next. The. Idea, is these technologies. Have, demonstrated. Some. Sort, of merit, in any of a number of different kinds of ways but. We don't really, know. Whether. Or not they can deliver in the, real, world operating. Environment. Which is of course what we need, them to be doing. So. The program, goes and this is what you'll be hearing about we. Identify, these technologies. We select the best of the best and then. We. Install. Those. Technologies. In a testbed location. Have a national, lab evaluate. And. Then at the end of the day if. They truly, D, deliver, we have a second, program. Is called pilots portfolio, that looks to. Employ. Those successful. Technologies. Those technologies, of the successful, field demonstration. Broadly. And. With that I will turn. This over so. Next line. Actually. On I'm sure, is this slide for me it. Is for you Kevin yes if you could want to introduce kind, of the partnership, that'd be great, okay. Thanks. I'm sorry, about that so. Yeah this is a great, slide, and.
And. I think it's it's. A really interesting, story. Not, just in terms of our partnership with Department, of Energy which includes. Our relationship. With the National Lab, but. Also with, identifying. Where. There are opportunities. To. Spur. Innovation, in. The marketplace around, those opportunities, and, then, of course to advance those. Into. Into, the world of our buildings so, in this case. Department. Of Energy's Building Technologies office. Who we've been working with for quite a number of years, developed. A specification, for a high-performance. Rtu. And this is based not so much on the federal, inventory, that is to say our GSA, inventory, we have some are to use they're not a dominant, portion of our of. Our HVAC, but. Out there in the broader, commercial. World they are this, is the dominant. Way that buildings are in fact heated and cooled. So. We. Collectively. Said this would be a great thing to to. Sort of develop a better you, know basically, a step, change in performance, there. Was a lot of research that went into why that it could occur why, that could occur cost-effectively. To, put that out to the market, and, really within two years we ended, up with, a, with. A manufacturer. Dyken that, actually. Was able to meet that aggressive. Spec so again 30 percent, of the spec was likes to 30 plus percent better. Than the. Phase, with the state of the, men. Are. So. I can let that they. Met that challenge we. Then. Identified. A testbed location. Actually there were a number of both commercial, and federal. Locations. Identified. And. We, we, identified. Wahi in Fort Worth Texas that's gonna be the subject, or, the the polka anyway, a bit, out please. Neckline. Very. Over the shirt a lot. Yeah. Good morning you, know I have a little bit of a cold and I'm hoping I'm coming through okay and I'll try. And get through this we talked major hiccups, next. Slide please so. As. You heard we're, going to talk about these. High-performance commercial. RT years and we'll define what we mean by that, now one thing I want to make sure is this presentation, uses, you, know specific, product, names you, know however it. Should be viewed as an endorsement of the product by me or. Pacific. Northwest National Lab and suddenly now Department, of Energy next, slide so. You. Know as most, of you know these packaged rooftop units are ubiquitous, and. They're used to condition, nearly. 50% of all commercial, floor. Space in the US, the. Popularity, comes because they're easy to install and relatively. Low, first cost you. Know however many, of, the, existing, units in the field have, relatively. Low seasonal, energy efficiency because. They were built with constant. Sweet. Drives and without advanced, controls to better coordinate, economizer. And ventilation, operation, and also, partnered operations, so. As you heard from Kevin you know in 2001, to, stimulate, the market, with. Higher performance, units, Department. Of Energy building technologies, office issued. A challenge to manufacturers. To build a. Unit, that is 50% more, efficient. You know based on ier. And, ier, is, basically, an integrated, energy efficiency, ratio it, could be viewed as a seasonal. Efficiency. Measure as opposed. To, energy. Efficiency, ratio which is a measure of efficiency at, a single. Indoor. And outdoor condition, so, the first RTO, compliant, unit was, introduced, in. A market, in late 2012. 2013. You, know currently, there. Are a number of manufacturers, who have products.
That Meet the. Our team challenge specification, and as, you seen in, the previous slide, daikon was the first one to introduce that. This. Presentation, will describe the major features. Of high performance, units, and the. Results, from, the field of. One. Particular. Unit. Next. Slide please. So. There. Are basically two, variations, of. High. Performance, RT, is the way that we define it you know the first and, most. Commonly. Used high performance, are to use all in the market today, you, know couples, a variable, speed. Drive, with. A supply, fan motor and, some. Of. These. Units also have variable speed drives on the outdoor fan motors. There's. At least one. Manufacturer. In, the US that actually. Sells. All. Variable. Speed that means the, supply fans, are variables, the outdoor, fans available speed as well as the compressor. So. It's the, one that you see on the right there so, most of these high-performance units. Modulate. Supply, fan speed. To. Meet a specific, zone, dry. Bulb temperature so. That's the supply fan modulation, and the. Units that have, variable. Speed compressors. They. Modulate the, compressor, speed to, maintain a certain, discharge. Air temperature, next, slide please. So. You. Know the one that unit that you are seeing here is the. One that was, tested. And. This. Unit, actually uses. Electronically. Committed, motors for fans. And then, it also has a variable, speed drive. On the compressor motor, so. These high performance, units. You. Know especially the, ones that are you. Know seven and a half ton or. Larger may. Have multiple. Compressors. For. Example, a seven-and-a-half ton unit might have it returned and a. Four and a half ton capacity, which, allows, these units to have three distinct, capacities. Three, ton then only one, compressed first compressor, is running you. Know four and a half ton when the second compressor is running and then, a seven and a half ton when all of them are running right. So. When. You have a. Unit. That has a variable. Speed, drive. And multiple, compressors, only. One of the compressor, is actually, variable, speed in the, rest of them are usually. Constant. Speed next, slide please. So. Um, and. And. I'm. Gonna cover, you. Know how we did, measurement. And verification, we, actually, did two. Different sites, and this. Presentation. Mostly. Will be based. On the site that we did in Fort Worth. The. One on the right that you see here although, we will present some results. From the supermarket. Site, in Florida as well so, ideally, when you're conducting a, measurement, and verification. Process. To estimate, savings, from. A retrofit. You. Know you want to measure the performance of, the existing, unit. For. A period of time typically. Nine months or longer then. Replace, that, existing. Unit with a new unit and then. Develop. A model for, the unit, that you replaced, using. The monitored data and. Then. You. Measure the performance of, the new. Unit, so. You, would then compare, the. Expected performance of the unit that was replaced now. That's the old unit using. The model and then, the actual, performance, of the new unit that you're continuing to monitor in the field so. However this approach takes. Twice as long to complete and also requires more, resources. You. Know we we didn't have either. Of them so we used an alternate, approach, to verify the performance, of these. New high-performance units. And compared, them. To existing. Standard units so, the Outland approach was, reasonable. Provides, reasonable results. If you're trying to compare efficiencies. Of two. Units so that's, what we did basically, simultaneously. Measure the performance so. Next, slide please. So. You. Know the measurement, that. We did was, simultaneously. For, over, ten month period, involved. Simultaneous. Monitoring, of an existing, standard, unit and a. High performance unit that. Was. Shown previously and, then, the, measurement, plan or measurement. Sensors, are shown in the slide on, this year right so. In addition to this the. Temperature, and relative humidity measurements. We, also measure, the airflow, for, the standard, unit which has a constant, speed supply, fan we. Did one time characterization. Of the airflow to, measure what, the airflow is in. The. Has, installed, condition, and then, for the high performance unit because the unit modulates, the supply fan so, we basically, did. A one time measurement, of. The. Fan flow, as a function, of fan speed because. We cannot measure fan, flow, or air flow, continuously.
In. The field so, but, we can measure the, speed of the fan so, if we can correlate the. Speed with the flow, then we. Know what the flow is at any given speed so. We did that one. Time and then, this allowed us to estimate. The cooling load on the coil and we also measured, the total energy consumed, by the unit which allowed us to estimate. The installed energy, efficiency, ratio for the both units next slide please. So. We. Did this as I said over a ten-month period, you know the graph, that you see here, is essentially. Daily. Energy efficiency. Ratio as a function of outdoor temperature. So the daily energy efficiency, ratio which is basically, a ratio of total cooling. Provided, by the unit, or the, course of a day to. The total energy. Consumed. By. The unit kilowatt hours or. The course of the day so, on average the, high-performance, unit, was about 16% more, efficient, and a standard unit at, least in this comparison. Next, slide please. So. You. Know comparison. Of. And. Before, we actually, did, the. Field test, we also did. A, lot of simulation, analysis, to, estimate, what the potential, savings would be across. The nation, you, know, comparing. The results from simulations. To actual, field performance is, always a bit tricky because, simulation. Models are always. Ideal, and don't. Reflect the true field conditions, you, know however the, simulations, serve, a purpose you know to provide, some, qualitative, compressions. Between two alternate. Designs. And. Some of the differences that you find, between simulation field, tests are because. You. Know the two units, that we tested, serve different loads, whereas, in simulation, they serve the same load and. Then there's there was also differences, of eer. Of. The. The. Standard unit in. The field it was 11.4. Which is slightly higher than, what, was used in the simulation so these all, of these lend, to. Some differences. In. Estimate. Of. Symptom. Savings, versus, what we saw in the field we. Saw a savings. Of 26%. This. Is you, know the 16% number you saw was in the difference. In the seasonal, energy efficiency ratio, but. In terms of energy it. Was 26%, reduction of, energy. For. The high-performance unit compared to the standard unit the, simulations, predicted, it would probably be around 40%, for. That climate, location and, for, that type of building. Next slide please. And. I'm. Going to cover some of the installation. Details and, you'll probably hear more from our GSA staff, from. Building. Additional. Details, you. Know each installation. Is going to be different so there. However, there are a few things that you. Can consider. While. If. You're considering, these type of units the challenge, units are generally heavier. Than. The, units that you're replacing and. May. Also have a different, footprint, than the legacy units so, you need to be aware of that because, the high performance units have, advanced. Controllers. And. Some of the installers, may, not be familiar with. Commissioning. And. It, could be a little bit tricky, or a, bit of challenge, however, you, know widespread, deployment of, these units should. Alleviate this, issue over time. Installation. May, sometimes. Require changes. To the ductwork as well as. Had. To be done in, that supermarket side but not here here. They had to reinforce the roofs and. You'll hear more, about that, later. Next. Slide please. Okay. Um. You. Know these results. Are. You. Know the, the. Payback results, are from another. Site, we couldn't compute that at. This site because we. Just didn't have a, handle, of the total installation cost because they there, were major. Modifications. For the roof that had. To be done so. But. We, were we were able to do. That for. The. Other side and, based. On the. Measurement. Of, data. Over a. 12-month. Period. We, estimated, that the simple payback was. Approximately. 3.8. Years. The. Interim the incremental, cost, we reported. That. Was reported by the building owner for this site was approximately. 6,000 as you can see however. This cost could vary depending on specific, conditions and, needs so. You need to be out of that in. Some regions of the country the high-performance, units, may be eligible for utility, rebate if that is the case that people pay back might.
Even Be lower so in, this particular case there wasn't any incentive, next. Slide please. So. If. You are considering. Installing. These units. The, best time to do that is, when, an existing unit reaches, its end of life so. Replacement. Replacing. A. Unit. That has reached end-of-life, with high-performance units. Should, be an option and high, performances, are also. An. Option for new. Construction if, you're building in brand new building so, modeling. Shows savings, are greater in hot and humid climates. Also. Units, with variable speed compressors. May provide better humidity, control, and, comfort. Next. Slide please. So. If. Your, unit doesn't, it's, not at the end of the life there, is also another solution. What. We call this advanced rooftop. Controller, so, let's say your unit, is maybe 5 or 10 years old and. This. Advanced. Rooftop. Unit controller is, an option, where. A variable. Speed drive is installed on a supplying fan motor and a, controller is also installed to manage the economizer and ventilation, operations, you, know more efficiently. You. Know we've done a, exhaustive, field. Tests. Of these, units. From. There we typically, found that the large units, larger. Units may be greater, than 5 tons that, run for longer periods of time over day you know maybe 10 hours are longer. Typically, have paybacks, less than 3 years, you. Know the cost information that, you see in, here is from a report that they did. Maybe. Five years, so, these are a little bit dated. I'm, sure the costs are probably lower. Than what we show now, I'm gonna show in this slide so. That's something that you need to be aware of also it's. Also worth noting that. Business. Cases have been made for. Installing these systems, even, in. Low, utility, cost. Areas such as in. Pacific, Northwest. And. Then also these high performance just. Like the high performance, units many, utilities also, provide rebates, to. Install these advanced, rooftop. Unit controllers, so. Next slide please I. Think. This is my last slide before I turn it over so. You. Know if you want to do a, comparison. Of two. Different rooftop. Units, you, know we do have a, RTO, comparison. Calculator. Which. You. Know shown on the slide. Where. You can compare, the performance of, two. Alternatives. However. There are some restrictions you know this only does cooling. Mode only it doesn't include eating mode and, then it doesn't have smaller. Units, the residential size units so. Note that this website, hasn't, been updated for. Several years now and currently. Is not being supported, by either PNL or do ii so. There's. No technical support if. You have any questions on, this however. Still. The useful, tool if you know how to use it and it's not that difficult you know if you just play with it you know you'll probably be. Able to learn how to use that quickly so. That's all I have, and I'll wait for the questions after. Everyone makes, their presentation. Thank. You. Go. Ahead so Frank. Went on, Draya are Frank slides next. Yes. Yes. So thank, you Frank. Stewart and Philippe for joining us and we'll. Be receiving feedback, from, the three of them and Frank will start off.
Next. Slide yeah good. Good. Morning everybody this is Frank Campania with, GSA, region 7 energy. And, sustainability, branch. I'm. In beautiful downtown Dallas. Today and not full worth but, I'm, close enough. I. Just. The only thing I really want to point out about this project is is the weight, of the unit itself and that was probably the biggest, challenge that we ran. Into, right. From right from the start this, unit weighs, approximately. 1,400. Tons and the existing, ream, wall he weighed 750. So we knew we had to address, that situation. We. Got with our structural. Engineers and we as. A result, they. They. Be. You. Know encouraged. Us to get a nanny involved. And get, design. Put together so, that we can reinforce. This, roof, so. What typically, what is a one-for-one, replacement turned, into, you. Know kind of a roofing. Project. For. Lack of a better description. If. It's. Lengthing, the, project. Considerably. Probably. You. Know by the time you had, your design, done and you went into construction, that probably delayed everything about a month and a half. But. It was, definitely. Needed, and as you can see here with that with the drawing. There. Was a lot, of steel. Installed. To. Accommodate, that anyway next slide please. Yeah. And I we. Invited, Stuart to come in because Stuart, was at. The time the. Building manager. But. Before I let's do a talk I just wanted to say we also invited, Selita, who is our integrator, that was probably. The, other. Biggest, challenge, that we had in regards, to. Monitoring. The, measurement. And verification process. We used our tritium, based building automation system, to collect. The data and, so. Felipe. Who. Is hired by our GC. To. Do. The integration was, very helpful in getting all. The new points, that the new. System. Supplied. And. I. Don't think Felipe that you really had too many challenges but, I know that there were a lot more points than. What the OL dream had and that's. Always very beneficial. Regarding. The. People who actually run the building the more. Monitoring. And the more sensors, and the more information of course helps. Them and that's what that new, Dyken unit provided, so Felipe. Did you want to add anything to that. No. Sir I mean the, integration was pretty simple, the. Only challenges. For the operator will be how. Many points as you mentioned already how many forms, they want to really see out. Of that integration. Other. Than that I mean. Integration. Was very simple. Thank. You and I know there were some issues some. Of the local controls inside the unit that we had to get the. Dyken people to come out and help us out and they were very, very. Quick to respond and we had. A good partnership, there. Thank. You Felipe Stuart do, you want to talk about the maintenance issues. I know you were the building manager and working with the local facility. Maintenance people, would. You like to share some of those what's, gone on with, that unit over the last two or three years. Stuart. Are you on mute. Well. I'll speak for Stuart I know. Stuart, works, in my department now so we interact, quite a bit and he was telling me that he reached out recently, to the building maintenance people, and I, think with the exception of two minor glitches, over, the last three years that unit, has been running flawlessly so.
I. Think by, and large were everyone's. Very happy, with. The way the unit. Is performing, so. Really. Don't have much more to say about the construction, side of it it was basically, a one foot one replacement if you take out the roof roofing. Project. Obviously. It's always a good idea to have all these things that says prior to go into construction so Andrea, I really don't have much else to say thank. You Frank and Stuart, I don't know if we can hear you now if you have anything else you'd like to add. Yeah. Sorry about that called again, mr.. Lampkin and so. I. Was, a property, manager, during this project I've, since become, a project. Manager underneath, Frank. But. Really, it was it was a pretty smooth. Project, other than the roof work, after. The unit was installed like. Frank mission there wasn't there. Wasn't really any issues. Operations. Or. Maintenance. Watch, it's. Been running, like it should and no. Issues. Okay. Thank you everyone, and. Let's start with question, number one. And what. I'll be doing is I'll be reviewing or referring. These questions, to whoever I think is the likely person to answer the question. Most. Often sent, of us that will be you but then Richard. Asked for everyone, so here's a link to the document, that was prepared on the it's, just reference, so I encourage. Everyone to look at Richards reference, that he offered, in the chat it. Gives more information about cool equipment, Brian. Asked at any other manufactures, meet the rtu challenge, I believe, in the presentations, when Abbas said that several other, manufacturers. Subsequent. That I can be my first, did. Meet the are key new challenge, specifications. Richard. Asks, how, many are to use are running in the US on, certain. Paths I don't know if you have access, to those kinds of numbers. You. Might be on you shrim bosses. You. Were going to respond. Sure um you. Well. I'm going to move on I'm going to guess that we. We. Don't personally, have numbers, on that but we, can look into that get. Ma asks, and I'm hoping shrinivas's part. Of this. Dittmar. Ask why, did, we compare ier. Instead. Of comparing ier. I'm, switching, screens on guys so. On yes, so we are but, we can't hear your Srinivasan, can you. Doesn't. Look like you're muted. Can. You. Speak. Up let's see if we can try and hear you if. Not maybe you want to call back in. Okay. I think we might need. We. Are not, looks. Like he's doing that now. Let's. Say I'm going to try to address questions that can be answered by someone else so let me jump around here. I'm. Going to actually share some other thoughts that people shared Gary, mentioned I'm sorry. Jenny, box yeah. Can you hear me no. Yes. We can great, oh I. Don't. Know what happened. Yeah. I got. The first one so all I, can tell you is that HRI. Publishes. New. Units that are sold but, it's really hard to estimate how many are to use are actually in the field, that's. Kind of a, hard, thing but. There are some proprietary, data sources, that might give that answer, but I don't have access to any of those. Okay. And then. Trent, Abbas the next question is so why did we compare e-r, instead. Of comparing I. Good. Question, so. Eer. Is actually, measured, at one, condition, it's, typically, 95. Degrees outdoor, 80, degrees, indoor and 50%. Relativity. Indoors so. That is that. Has been metric. For a long time however, that, really, doesn't capture, the. Seasonal, performance of the unit because remember, a lot of these units actually don't, operate, at, 95, degrees. Doors every, day you, know they're operating, at parlor condition, so. There. Is a new metric, just like the, seasonal. Energy efficiency ratio, for, residential units. For. Commercial. Units it's integrated. Energy efficiency, ratio, it's basically, a a. Performance. That is measured at four different points and, then averaged, and that's. A better metric that, would give, you a better sense of what the unit is performing, or an, annual. On. An annual basis so that's the reason why they. Chose ier. Rather. Than eer and the. Current manufacturing, standard, requires an ier requirement. As well in addition to year. And. Then sort of ask um Gary. Asked the, payback is not appear to account for the structural mitigation, cost is, that correct, yeah.
So Remember. Paybacks. That the payback that we showed. Was, not for. The. Fort Worth building, but for another. M&V. That we did in a supermarket, in Florida. There, they did not have to do any structural, modifications. The. Existing. Roof could handle these, high-performance units. Without any. Change so, the, incremental cost was basically, the incremental cost for the. High-performance unit versus if, the BOD is standard in. Okay. Thank you and then next question is would you please comment on the degree of noise. From, these RT units and our. In, any suggestions. You may have to, mitigate, the. Noise yeah so yeah. All that GSA. Staff. Answered that but these, units, because they're variable, speed or they're less noisy. Than. The. Traditional. Units. However. I'll turn, over to. Stewart or Frank, to. Make. A comment on what they have, experienced. Well. I, was, I'll just add yes they're very quiet as compared, to that Rheem unit, with. It you know running, in a lower speed. It, just, goes without saying that the there's less noise associated, because. Of that functionality, so I would, definitely agree with you. Seward, anything uh I. Just. Same. Thing with Frank I concur it's, it's a, lot. Quieter than the normal r2 unit. Okay. Thank you. Let's. See next, item, Theresa, also. Shared let's try to people want to look up the link an, evaluation, of a jacket revel in a field, test in Sacramento, and then. Monty, had asks. Looking only at the capital, cost. To. Replace an arch in you not to incremental, cost what does he expect to pay back range at ten cents a kilowatt-hour i. I. Can, tell you that you know the best sources if you go to the arc to you chance calculator, and put those numbers and see a dog. Depends, on the load on the building type of the building location. Of the building it's. Hard to say. Right. Thank. You. Reginald. Asks, was. The roof modification, accounted for in the payback calculation. As. We indicated before the payback calculation, that was offered in. This presentation, was for the Florida. Supermarket study. Not this study. Let's. See. John. Beat Alaskan PRT you come with the controller and sensors, I believe the answer to that is yes, which. Is just back earlier. Before the rtu challenge friend of us confirm, this for me prior. To the RC u challenge there was a mechanism by which you can add, controllers. The sensors to are to use and that I think you showed a slide that shared. The results from that, yeah. So these. Are, to you high, performance, are to use because. There. Doing, lot more controls, than. The. Standard units they do come with controllers. And. They also, support. Integration. To the, existing, building automation systems, like like. We did at Fort Worth, but. The older ones may, or may not have a, controller. Thank. You. Jack. Asks, and you're testing do you find that the unit performed, according to the rated ie we are. Should. It be dead again. Did. You find it. Performed, according to its grade into ier. It's. So. Ier, is a. You. Know a rating, condition, and there were specific indoor. And outdoor conditions that, the. Tests are done so. It's really hard to do that kind of a. Estimate. In the field 4ier. You. Know what we did was basically, estimated. A seasonal. Efficiency. Over. The monitoring, period at. Every, load. That we saw so. The. Season efficiency, that we reported, you, can't compare, that to an ier. Thank. You Mike. We, will be sending out the slides afterwards. And then. James asks, was, there any other than the roof modifications. Was. There any difference in installation and equipment, costs between. The rebel, and the. Rebel. Are to you and the original. Are to you and I would imagine so. We've got two components in. Difference, in installation, cost then. There is there any difference in the equipment cost. With. That Renda towards me Mike or, why. Don't you take care of yes you, can answer it that would be great. Well. I would, just say that there, had. To be some modifications.
To The ductwork. Which. Was you. Know that's a little bit of an added cost but. Nothing. What. You, know that's compared, to what the roofs modification. Cost so it. Was very little, to nuts and none. Besides. A basic rooftop. For rooftop replacement. Okay. I think you do, either you're about 70 idea of the cost just, unit. To unit I. Would. Have to go back and, look and look at those notes I don't, have them off the top of my head. Okay, thanks, and, then. Jerry axe. Haft. Under, the RTT is running and how often you. Have to perform maintenance, besides. Changing filters. So. Any. Maintenance, differences. Between the. Rebel. Unit and the incumbent. Unit. Stewart. Once you take that one. Yeah. So, this is stirred. The. You. Know we have to look at the data to see how often it's been running. But. As far as the maintenance all they had to you, I think, the unit's been in for. Two. Or three years but. You. Know all I've had to do is the the, basic maintenance of change in the filters out. There. Hasn't been any, replacements. Or anything that are taking place so far. Other. Than the filters themselves, okay. Thank you and. I would just add Mike that we have we have these units. On a schedule, with our building automation systems, so they don't run 24, hours a day but. You, know in this part of the country they do run quite a bit sure. Okay. Thank you. Francis, asks, how do the tests are to use, deal. With oil fouling on the inner heat absorbing, coils, that. Will rob are to use a cooling capacity, over time. For, that or I. I. Don't think these are any, different, from standard units, in. Terms of the, technology, that. The the compressive, technology, and the heat exchanger technology, so, I'm guessing, you know whatever. The. Standard units face the high-performance, units probably will have similar. Things. Okay. Thank you. And. Then Jerry. From the testing with the economizer, cycle, included, the energy savings calculation. Well. In. Fort Worth it wasn't, because you. Know, the standard, units, was, 100 percent recirculation. And. Also, the climate is. Also not conducive for economizing. And in. Florida. It. Was only economizing. For. A fraction. Of the time you, know during the winter periods. And. That just because of the weather. Okay. Thank you and, last question mark. Asks, if. The space experience, any room air distribution problems. With. The new variable speed supply fan are to you considering, the ductwork and supply diffusers, were. Designed for a cost to flow HVAC, system. And frankly I may speak to some of the ductwork modifications. Yeah. I, think. The, experience, was a good one it was I think it was improved. Over, what the baseline, unit, had, and. Met. And many, instances, the set, points, were, reached sooner, and, unit. Was able to. Use. Less energy where. The other unit was still trying to catch up and we reach that set point so, I'm. Not sure if I'm answering your question mark, but I. Felt. Like the new unit used, a lot less energy to get to where it needed to go. Okay. Thank You, Andrea. That's it for the questions so, I'll turn it back over to you. This. Webinar. Is available for, continuing, education learning, units and to receive credit, you. Want to complete. The short survey, that you should be receiving shortly, and, upon completion you'll. Be getting. Credits and if you don't please, reach out.