< Previous20 OCTOBER 2019HIGH-PERFORMANCE HVAC TODAYThe October Power-Pack Is Ready!We hope you were able to take advan-tage of all the great tools from your Sep-tember PowerPack. As you know, last month we focused on preparing for the Fall. This month we provide you with content and tools fo-cused on heating season tune-ups.For October 2019 your PowerPack fea-tures the following: z How to Perform Draft Interference Testing (Recorded Webinar) z Carbon Monoxide Visual Each monthly PowerPack is only avail-able for 30 days. So go online and get started today. The download is located at ncilink.com/PwrPak.If you have any questions, or if you are unable to access any of the tools in this program, please contact your Customer Care team at 800-633-7058.Summit 2020 Early-Bird Rates Available Now!If you haven’t already done so, mark your calendars for April 6-9, 2020. That’s when the National Comfort Institute (NCI) High-Performance HVAC Summit 2020 (gotosummit.com) returns to the We-Ko-Pa Resort & Conference Center in Phoenix, AZ. Summit 2020 is shaping up nicely. Its theme is “Coach Your Team to High Per-formance.” Attendees will learn skills to better communicate with co-workers the expectations and goals of becom-ing performance-based.The core NCI conference includes two days of breakout sessions topped off with the annual NCI Awards Ceremo-ny. And the best part – you can regis-ter right now for the conference and save hundreds! Plus, as members you can apply your NCI Bucks towards the event and earn Bucks back.So don’t miss out. Simply go to the link (ncilink.com/Summit2020Reg) to take advantage of the Early-Bird rates and get your team set for April 2020. Once pre- and post-con options are available, you’ll be the first to know.Questions? No problem. Call Customer Care at 800-633-7058.Welcome New Members!Membership in an organization like National Comfort Institute (NCI) is a step toward becoming a Performance-Based Contracting™ firm. It is a commitment that has an ex-traordinary impact on your business and your team. So, it is our pleasure welcome 21 new members, so far, in 2019.We are pleased you all opted to join our family and look forward to hearing from you and even meeting you in April 2020 at our annual High-Performance Summit, which is being held in Phoenix, AZ.If anyone has questions about their membership or the Summit event, please call our Customer Care line at 800-633-7058.NCI MEMBER UPDATEWELCOME New MembersInspection Form (Download) z SafeMaxx CO Test Report (Download) z Heating System Temperature Measurement Procedure (Download) zCold Feet? Heating Postcard (Download).We think you’ll find these tools and training materials very helpful as you prepare for your heating season tune-ups and continue to grow your High-Per-formance HVAC business.Don’t forget to share this month’s Pow-erPack with your entire team!OCTOBER 2019 21HVACTODAY.COMHVAC SMART MARTAdvertiser IndexHIGH-PERFORMANCEHVAC TODAY TMAD INDEXBaker Distributing Company | BakerDist.com ............................................................................7 Dwyer Instruments, Inc. | www.dwyer-inst.com .......................................................................2 Goodman Manufacturing | www.GoodmanMfg.com .............................................................4Jackson Systems | www.JacksonSystems.com ........................................................................10 Lazco Corp. | www.LazcoCorp.com .................................................................................................6 R.E. Michel Company | www.REMichel.com ..............................................................................13The New Flat Rate | www.TheNewFlatRate.com .....................................................................21 To Your Success | ToYourSuccess.com ........................................................................................ 21United Refrigeration Inc. | www.uri.com ................................................................................... 19To Subscribe to High-Performance HVAC Today:ONLINE: Visit HVACToday.com/subscribe for a FREE digital subscription.PRINT: 1 year/$72; single copy $7. Canada: 1 year/$92; single copy $9. Payable in advance with U.S. funds. Prepaid subscriptions may be sent to: High-Performance HVAC Today, PO Box 147, Avon Lake, OH 44012. Phone: 440-949-1850; toll free 800-633-7058; Fax: 440-949-1851, or visit HVACToday.com/subscribe to order online.PublisherDominick GuarinoEditor-in-Chief and Associate PublisherMike WeilArt DirectorConnie ConklinOnline Development DirectorBrian RosemanCirculation ManagerAndrea Begany- GarsedEditorial AssistantMarge Smith22 OCTOBER 2019HIGH-PERFORMANCE HVAC TODAYIn other words, on older systems, we had a lot more leeway within that sweet spot. This is not the case with newer, high-efficiency equipment.HIGH-EFFICIENCY EQUIPMENTFigure 2 illustrates the bell curve and sweet spot on today’s high-efficiency heating and cool-ing equipment. To achieve higher ratings, this equipment must work within a much tighter range. This means airflow needs to be dialed in much more accurately. On DX systems, refrigerant charge must also be very precise, either weighed in properly, or by hitting exact subcooling and superheat num-bers using digital gauges. Precise charge for max-imum efficiency can only be achieved when there is proper airflow through the system.Variable Refrigerant Flow DX systems are some-what more forgiving when it comes to airflow, but even these systems will never reach design capac-ities and efficiencies without proper airflow. The same applies to newer high-efficiency furnaces.These bell curves are not designed to be precise efficiency curves for every system, rather they are meant to illustrate the differences between older equipment and their newer counterparts. Are your field people using state-of-the-art dig-ital test instruments and modern testing methods to test and adjust today’s more “sensitive” equip-ment? Learn to hit the sweet spot on your instal-lations, and give your customer the comfort and efficiency they deserve. I t’s more important than ever to measure and tune performance on HVAC systems with high-efficiency equipment. Getting equip-ment to achieve its design capacity is highly dependent on two key variables:1. Airflow across the heat exchanger (in fossil fuel furnaces) or across the indoor coil (in Direct Ex-pansion (DX) air conditioners and heat pumps).2. Proper fuel/oxygen ratios and venting in gas fur-naces, and refrigerant charge in DX air condition-ers and heat pumps.In order to deliver rated capacities from heating and/or cooling equipment, airflow must be cor-rect. Either too much or too little airflow will keep equipment from operating efficiently at design ca-pacity. Essentially, there is a sweet spot at which high efficiency occurs.OLDER LOWER EFFICIENCY EQUIPMENTFigure 1 illustrates this “sweet spot” in the form of a bell curve with the y-axis representing efficien-cy, and the x-axis representing airflow. Older, less efficient equipment has a fairly wide “sweet spot.” What this means is there is a fair amount of for-giveness with 70 to 80% furnaces and 8 to 12 SEER equipment. On older DX systems, analog gauges were good enough to measure things like superheat and sub-cooling. On older fossil fuel equipment, there is much more forgiveness in terms of gas pressures and oxygen, as long as CO levels are under 100 ppm and stable. Dominick Guarino is publisher of High-Performance HVAC Today magazine and CEO of National Comfort Institute, Inc. He can be reached at domg@ncihvac.com ONE MORE THING...By Dominick GuarinoThe High-Performance Sweet SpotAirflowEfficiencySweet SpotFigure 1. Performance in older equipment.Figure 2. Performance in newer high-efficiency equipment.AirflowEfficiencySweetSpotNext >