< PreviousTURN DATA INTO DOLLARS Stored data is to the business as stored seed is to the farmer. Without seeds, the farmer can’t grow a crop. Without data, the business owner can’t grow customer delight and prof- its. You must act on the data like farm- ers must act on the seed. If you know what to look for, mining a database to find the best sales oppor- tunities is simple. What could you do with a list of current customers with 18-plus-year-old equipment hooked up to a failing (57% efficient) duct sys- tem? If I were in sales, I would love to work that list! The nice thing is, when you proac- tively work your database, you can decide when you need to “plant the seeds” that can sprout and turn into profitable sales. When outside tem- peratures are extreme, you don’t need more leads; you need more people to get the work done! When it’s mild out- side, that’s the best time to take ac- tion on your stored data and begin the educational sales process. Once again, someone in your busi- ness must be responsible for acting on your stored performance data. You must assign someone to farm your performance database for more op- portunities to delight customers and improve profits. Like an unplanted seed, it will produce no fruit unless planted and nurtured by the farmer. ENCOURAGE AND MOTIVATE YOUR TEAM It is common to find discouraged technicians because they don’t see any benefit from the system perfor- mance data gathered on their service and maintenance calls. Not seeing the get the job done. You must actually do something with that information to turn it into meaningful results. You need to treat the data like cold, hard cash. Why? Because you can convert information gleaned from the data to more work with just a little effort on your team’s part. MANAGE YOUR HIGH- PERFORMANCE DATABASE Unfortunately, most static pressure measurements are handled very poor- ly in the office. Without a solid plan, these golden opportunities get stacked up in a desk drawer and fall through the cracks. This results in frustrated customers, unhappy service techs, un- employed comfort advisors, underem- ployed installers, and reduced compa- ny profits. The best solution is a robust database. Many modern service manage- ment software systems let you create custom fields. If your current system allows this, you should add at least four static pressure fields on the service call record to capture static pressures for the return duct, before the blower, after the blower, and the supply duct. Of course, NCI’s ComfortMaxx™ system is the best place to capture this performance data because it can pro- duce meaningful reports to educate customers about your findings and recommendations. Whatever method you use, someone in your business must be responsible for maintaining this information gold- mine. If nobody is watching your valu- able database, the information will be useless, and you’ll miss out on many opportunities to delight customers and grow your business. SALES David Holt to Lead Summit 2023 Discussion This article is based on an upcoming discussion moderated by David Holt at National Comfort Institute’s 2023 High-Performance HVAC Summit in Branson, MO. In its 20th year, this event focuses on the High-Performance HVAC Contracting segment of the industry and promises to be something you and your team should not miss. The focus is how high-perfor- mance starts with service. If you haven’t done so, sign yourself and your team up. Plan to join your peers from across the country in Branson, MO, from April 17-20. You can learn about upcoming sessions, special events, registration savings for members, and more at gotosummit.com . Also, book your hotel rooms as part of the NCI discounted block. David Holt is NCI’s director of national accounts and an instructor. You can reach him at ncilink.com/ContactMe with any questions or comments. HVAC SUMMIT 2023 HIGH-PERFORMANCE 20 APRIL 2023HIGH-PERFORMANCE HVAC TODAYAPRIL 2023 21HVACTODAY.COM activities that result in greater success. Assign someone on your team to track, monitor, and publicly report lead and lag measures. If nobody is responsible for this vital activity, you will miss out on the incredible bene- fits that the high-performance HVAC approach has to offer your customers, your employees, and your company. WANT TO LEARN MORE? High-Performance HVAC Sum- mit 2023 attendees will benefit from the “wisdom of the crowd” as participants discuss how they prop- erly manage and use the informa- tion collected on repair and mainte- nance calls to drive customer delight and increased profitability. See you in Branson! delight scores, average sale price, and profitability are all critical lag mea- sures that will not occur unless the lead activities are performed. Shar- ing lead and lag measures with your team can encourage and motivate them to continue performing required benefit is an unfortunate error. Every- one needs to see measurable results from their efforts to encourage and motivate them. “Lead measures” track the criti- cal activities that drive (or lead to) the accomplishment of an important goal. What leads to delighted customers and business growth? For High-Per- formance HVAC contractors, stat- ic pressure measurement is one criti- cal activity to track. While many more critical activities should be monitored, the performance of this simple activi- ty predicts the success of goal accom- plishment. It is influenced directly by the service team. “Lag measures” track the success of your most important goals. Cus- tomer education contacts, customer 22 APRIL 2023HIGH-PERFORMANCE HVAC TODAYAPRIL 2023 23HVACTODAY.COM temperature would rise, and a person would be- come ill or die. Some of this internal energy is released as work (moving about), but most energy is converted to heat, which then transfers to surroundings. HEAT GENERATED BY A PERSON IS RELATED TO THEIR ACTIVITY LEVEL Heat Transfer to the Environment: The hu- man body operates in- ternally at approximate- ly 98.6°F. Normally, the body’s “cooling system” controls the body tem- perature so that it is al- ways within a few tenths of a degree of that temperature. The skin surface temperature is typically cooler, approximately 86°F. The primary rule for keeping a person comfortable is maintain- ing the environment so that the heat generated by their metabo- lism can be rejected at a comfort- able rate. If you allow people to lose heat too fast, they will shiver I n the late 1980s, our family spent a winter living in an old farmhouse in the Catskill Mountains of New York. Portions of the house date back to 1896. We guessed this from the headlines of newspapers we pulled out of the old horsehair and plaster walls we were removing in the remodel. A fuel-oil boiler in the basement heated the house by circulating hot water through baseboard radiators. Our preference was to be near one of these ra- diators when a good old-fashioned blizzard was howling outside. I can still remember standing in front of one of the rattling, multi-paned windows shivering in my wool sweater, even though the soup on the kitchen stove was boiling, the wood stove was almost glowing, and the baseboard ra- diators kept the room a comfy 70°F or so. UNDERSTANDING COMES LATER IN LIFE I only understood the radiant loss I was expe- riencing and its profound impact on human com- fort much later in my life. A great many factors, both physical and psychological, are associated with being or feeling comfortable. The heating and air conditioning practitioner must be concerned with those factors affecting the conditions which provide a healthy and ther- mally comfortable environment for people. To better understand how “comfort” works, we must discuss how the human body handles heat. Food’s energy (calories) is re- leased when it’s oxidized or, in a sense, burned inside the body. This process of internal heat gen- eration is called metabolism. In- ternally generated heat must be dissipated. Otherwise, body How Room Surfaces Affect Comfort By Paul Wieboldt TECHNICAL Metabolic Rate24 APRIL 2023HIGH-PERFORMANCE HVAC TODAY inadequate to remove all the excess heat from the body, the deep body temperature will continue to rise, causing the sweat glands to open. As the skin’s surface becomes moist, ad- ditional heat is removed as the sweat is evaporated into the surrounding air. In the process, the skin surfaces are cooled. The amount of evapora- tion (cooling effect) from the skin de- pends on the humidity and velocity of the surrounding air. The higher the humidity, the lower the evaporation rate; increasing air motion tends to in- crease the evaporation rate. Heat Loss by Radiation — Ra- diation is perhaps the least under- stood method of body heat rejection, but it is a significant mode of heat loss. The human body receives heat energy from any surface warmer than the skin and loses heat to any surface cooler than the skin. A classic example of radiation heat transfer is the heat received from a glowing fireplace. In this process, your body is warmed directly by the radiant energy emitted by the fire and not by the air that is in front of you. For radi- ant heat transfer to occur, your body must “see” the radiating surface. As in our real-life example introduc- tion, in the winter, the inside surface of a large window may be much colder than a person’s skin surface tempera- ture. Hence the body would radiate considerable heat to the cold window. A person may shiver in front of the large window even though the room air temperature is normal and body heat loss by convection and evaporation is minimal. To compensate for the high radiation heat loss, a person might wear a sweater or raise the thermo- stat to increase room air temperature and reduce convective and evapora- tive heat loss. Effect of Surrounding Tem- perature — The curves below illus- trate how the amount of heat rejection by each heat transfer mode can change depending on the surrounding envi- ronment. As the air temperature in- creases, body heat loss by evaporation increases, and heat loss by radiation and convection diminishes. At 70° F, only 100 Btuh is lost by perspiration and 300 by radiation and convection. At 90° F, the situation re- verses; less heat is carried away by ra- diation and convection, and more heat is carried away by evaporation. Building Envelope Affects Hu- man Comfort —The quality of the building/room thermal envelope is a significant factor in providing human comfort. Insulation, for example, can reduce radiant heat loss by increasing inside-wall surface temperatures. The illustration on the next page shows the temperature gradient through an insulated and uninsulated frame wall. On frigid days, the inside un-insulated wall surface temperature might be as low as 61°F while a ful- ly insulated wall at the same outdoor conditions would be over 71°F. This means a person would radiate less heat to an insulated wall than to an uninsulated one. It also means that and shake. If they lose heat too slowly, they get warm and perspire. The human body’s control system reduces heat transfer to the surround- ings when the body temperature be- gins to drop. It increases heat trans- fer when the body temperature rises. Heat is transferred from the body to its surroundings by convection, evaporation, radiation, and (to a small extent) conduction. Heat Loss by Convection — As our body temperature rises from above 98.6° F, our blood vessels near the skin surface expand, allowing more blood to flow to the skin. Skin temperature rises due to hotter blood, increasing the heat lost to the air be- cause of the more significant skin-to- air temperature difference (Delta T or ΔT). The skin is the body’s heat re- jection layer or “radiator.” The temperature and velocity of the air moving over the skin directly affects the amount of convec- tive heat loss from the skin. Heat Loss by Evaporation — Should the heat lost by convection be TECHNICAL (Room Surfaces continued on page 26)APRIL 2023 25HVACTODAY.COM26 APRIL 2023HIGH-PERFORMANCE HVAC TODAY TECHNICAL Effect of Winter Humidifica- tion — As noted, indoor humidity does affect the rate of body heat rejection by evaporation. However, if only residen- tial and office environments are con- sidered, the effect of significant chang- es in indoor humidity is minimal. During the heating season, a change from 20% to 60% RH may go practi- cally unnoticed by most occupants. The critical point is that while humid- ity is a factor in heating season com- fort, the human body is more sensitive to slight changes in air and surface temperatures. Of course, during the cooling sea- son, people have a low tolerance for high humidity, and humidity control becomes more critical. Effect of Velocity –The human body is sensitive to air movement, especially at rest, like watching TV, reading, working at a desk, etc. A draft happens when air with a specific com- bination of air velocity and tempera- ture causes a sensation of coolness, hence the discomfort. How fast must air move to cause a draft? It depends on which part of the body is affected by the moving air stream. The chart below outlines comfort zones for the neck and ankles for a range of air temperatures and air ve- locities. At 72° F, air moving at 30 feet increasing or decreasing surface tem- peratures by 1°F is the same as in- creasing or decreasing room air tem- perature by 1°F in terms of the comfort achieved. Mean radiant temperature (MRT) is one way to measure the effect of inside surface temperatures. The MRT can be derived from equations, which consid- er the various room surface tempera- tures, or by using a “globe” thermom- eter illustrated in the figure below. Experts in measuring human com- fort often combine room air tem- perature with a room’s mean radiant temperature to create an improved comfort index. This new index is called the “adjusted dry bulb” tem- perature. It is calculated by averaging the room air temperature and mean radiant temperature. For example, the adjusted dry-bulb temperature for a room at 75° F with an MRT of 71 would be: The fact that the building enve- lope’s thermal characteristics are so important in maintaining comfort means that the air distribution de- signer must consider inside surface temperatures (especially the amount, type, and location of glass or poorly insulated walls). designing an air distribution system that provides a comfortable environ- ment would be easier. For example, a well-insulated enve- lope would provide a winter environ- ment comprising 75° F room air with inside wall surfaces at a little below 70° F. The illustration below shows how a person seated at rest might lose heat to his environment. About 200 Btuh would be lost by radiation to the cold- er walls and convection to the room air; perhaps 100 Btuh would be lost through evaporation. If a large amount of glass was in- stalled or the walls were uninsulated, the wall surface temperatures would be less than 70° F, and the person would lose more heat by radiation. Mean Radiant Temperature — Laboratory tests show that surface temperatures are as important as room air temperature to overall com- fort. In fact, researchers suggest that (Continued from page 24)APRIL 2023 27HVACTODAY.COM TECHNICAL and architects to use the best glass pos- sible in their window choices. Radiant loss seems to be little under- stood in our business, but as you can see, it needs to be at the forefront of our understanding in order to provide our clients with cozy comfort! the ceiling. Lights and appliances can produce their own local air currents as well. Such air motion is referred to as natural convection (air) currents. While standing in front of that wavy- glass farmhouse window listening to the wind howl and watching the snow flakes swirl, it had not occurred to me why I shivered but it did stick firmly in my memory. In my heating and air conditioning duct designs, it effects where I locate grilles in the floor or ceiling of a room. I locate them in the vicinity of a window whenever possible so the warmest air will be there to offset the radiant glass loss we all experience. It effects my passion for well-insulat- ed walls and warm floors. It also effects my efforts to convince home owners per minute (fpm) would be outside the comfort zone near the neck and con- stitute a draft. That same 72° F air around the an- kles could be moving at 90 fpm or more and would not be felt as a draft. As the air gets cooler, velocities must be reduced to avoid discomfort. Natural Convection —Usual- ly, air motion in a room results from “natural” conditions. In winter, room air contacts cold glass and cold exte- rior wall surfaces. This cools the air. Since the cooler air is heavier, it moves down the wall and across the floor. In summer, the reverse occurs. Room air in contact with the warmer glass and walls is heated and becomes lighter. This air moves upward and across Paul Wieboldt is president of Tradewinds Appropriate Technologies, Waco, TX. He has done most things when it comes to home remodeling and construc- tion. He also started a pri- vate school, worked for a curriculum developer, and fell in love with teaching. In the mid-1980s he moved to Texas and began his ca- reer in HVAC. Several years later, he discovered NCI and was able to combine his experiences into a teaching focused on environmental comfort and health. Contact Paul for more information at paul@manualjdesign.com.28 APRIL 2023HIGH-PERFORMANCE HVAC TODAYLLC. The next class is scheduled for April 25-27 at RE Michel Co. in Baltimore, MD. Check out future training in 2023 by clicking here . Questions? Be sure to call NCI’s cus- tomer help line at 800-633-7058. DID YOU KNOW ... ? Members of National Comfort Insti- tute (NCI) enjoy many benefits. One of them is a monthly download/access fea- ture known as the PowerPack. Each month’s PowerPack is designed to help members explore different tools they can use in their high-performance contracting businesses. These tools consist of step-by-step instructions for using various test in- struments. Plus there are articles on ev- erything from how to implement perfor- mance into a company, to the best ways for selling air upgrades, and more. The PowerPack also provides access to a variety of NCI online-based training modules, and so much more. None of these tools are available to non-members. As a member, if you haven’t taken ad- vantage of your PowerPack tool benefits, don’t wait. Go to ncilink.com/PwrPak . If you aren’t a member but are interest- ed in learning more, visit ncilink.com/ NCIMembership or call 800-633-7058. DO YOU KNOW ABOUT AIRMAXX™ AND AIRMAXX LITE™? In this digital age, having software to help with calculating equipment-de- livered airflow and understanding its overall performance is more important than ever. National Comfort Institute members have some amazing advan- tages if they use the organizations Com- fortMaxx family of software for these purposes. AirMaxx™ is a mobile app that is in- cluded for all NCI members or Comfort- Maxx™ subscribers. With it, you can cal- culate the following: z Total External static pressure z Supply Duct static pressure z Return Duct static pressure. AirMaxx Lite™ is a free-version of Air- Maxx that is open to the public. It doesn’t do everything that the full version does, but is good enough to help your field team calculate TESP and communicate HVAC equipment delivery performance relative to its rated static pressure. AirMaxx also easily communicates equipment performance in delivering airflow relative to what it is designed to deliver. It can identify which compo- nents are causing stress to that airflow delivery. The cool thing about AirMaxx is that once its downloaded to a mobile device, it does not require a WiFi connection! Both of these apps are Android and iOS friendly. AirMaxx is cloud-based software that requires NCI membership and a subscription. Learn more by calling the NCI Custom- er Care line at 800-633-7058. NCI ANNOUNCES A NEW CLASS National Comfort Institute (NCI) has a new training course that will help HVAC contractors learn how to accurately com- plete four stages of system design. After all, a High-Performance HVAC system starts with the right design. High-Performance HVAC Design and Redesign focuses on NCI principles as well as ACCA (Air Conditioning Con- tractors of America) Manuals J, S, D, and T using the Elite RHVAC software package. This is a three-day course that has seven 50-minute learning modules. It is taught with a live instructor, uses inter- active discussion, and includes many visuals to help attendees with both writ- ten and hands-on exercises. Though not a certification class, con- tractors and technicians who complete this training will be able to use com- puter-based software to design proper- ly-sized HVAC systems that conform to NCI performance-based principles to en- sure an optimized system. This is a stand-alone course that re- quires basic computer literacy. The course is designed for HVAC contractors, company leaders, technicians, installers, salespeople, and more. The course was first taught earlier this month in Austin, TX by Paul Wieboldt of Tradewinds Appropriate Technologies, NCI UPDATE APRIL 2023 29HVACTODAY.COMNext >