< PreviousRegister today at GoToSummit.com or call 800.633.7058SUNDAY, APRIL 5 7:30 am - 2:00 pm Golf Outing with LunchMONDAY, APRIL 6 Optional Pre-Conference Events and Training: 9:00 am - 4:00 pm Increase Closing Rates and Profits with Perfect Pitch 9:00 am - 4:00 pm Step Up to High-Performance HVAC! 9:00 am - 1:00 pm Women in HVACR Western Regional Meeting 8:00 am - 4:00 pm Advanced Air Diagnostics Recertification Class 8:00 am - 4:00 pm Refrigerant-Side Performance Class (Part 1) 4:15 pm - 5:00 pm Summit and Membership Orientation Meeting - All Welcome! 6:00 pm - 8:00 pm Summit Week Welcome Reception - Sponsored by GoodmanTUESDAY, APRIL 7 7:00 am - 9:00 am Breakfast and Special Interactive Opening Session 9:15 am - 10:45 am Breakout Session 1 - Workshops 11:00 am - 12:30 pm Breakout Session 2 - Workshops 12:30 pm - 1:30 pm Luncheon and General Session 1:30 pm - 3:00 pm Breakout Session 3 - Workshops 3:30 pm - 4:30 pm Idea Meetings: Lead Generation and Sales 4:30 pm - 5:30 pm Panel Discussion 6:30 pm - 8:00 pm NCI Partners Trade Show and ReceptionWEDNESDAY, APRIL 8 7:00 am - 9:45 am Breakfast & General Session 8:00 am - 9:00 am State of NCI and the High Performance Industry with NCI CEO, Dominick Guarino 9:00 am - 9:45 am Keynote Speaker: Ryan Kohler, Hire Dimensions 10:00 am - 11:30 am Breakout Session 4 – Workshops 11:30 am - 1:30 pm NCI Partners Tradeshow and Luncheon 1:30 am - 3:00 pm Breakout Session 5 - Workshops 3:30 pm – 4:30 pm General Session with Idea Session Winners and Prize Drawings 4:30 pm - 5:00 pm Closing Remarks with NCI President, Rob Falke 6:00 pm - 7:00 pm Member Appreciation Cocktail Reception 7:00 pm - 9:00 pm Awards Banquet and Presentation CeremonyTHURSDAY, APRIL 9 Optional Post-Conference Training: 8:00 am - 4:00 pm Refrigerant-Side Performance Class (Part 2) 8:00 am - 4:00 pm Advanced Combustion/CO Diagnostics RecertificationSchedule of EventsFEBRUARY 2020 21HVACTODAY.COMOur industry thrives on the integrity of technicians taking accurate measure-ments. But when technicians don’t understand the instruments, or if they use them improperly, that can lead to collecting incorrect data. Bad data leads to HVAC systems that do not operate correctly.When I’m teaching new air balancers at Aira-digm Solutions, I make sure they understand the measurements they are obtaining, and I teach them to ask the question, “does this measured value make sense?” Below is a list of some of the most common air-side mistakes made by new technicians, and the recommendations I give our techs.INSTRUMENT MISTAKE 1: Using Capture Hood to Measure Sidewall GrillesI had a technician measure six sidewall grilles in the corridor of a school entrance. He chose to use a capture hood and reported reading 3500 cfm. This was well over the 2000 cfm design.The measurement didn’t make any sense. The unit was located on the roof, two floors above the grilles. It seemed unlikely the engineer miscalcu-lated the ductwork that much. Additionally, we were finding most of the other systems on this project had low airflow performance.I instructed the technician to traverse the unit right before the grilles, and he measured 1950 cfm. This measurement made much more sense. We learned instrument mistake #1: capture hoods read higher on sidewall grilles. The capture hood is an amazing instrument, and I believe the TAB industry would not be in such demand if these hoods were not accurate and easy to use. But in the case of sidewall grilles, it failed to give the technician the right measurement. Why?The capture hood typically uses a 16-point veloc-ity grid to measure air velocity. The grid does not take 16 individual readings like you do with a tra-verse. Instead, the velocity grid has 16 holes that feeds into a top (high) side chamber, and 16 holes that feed into a bottom (low) side chamber. The air blends together to give one high side reading and one low side reading. By mixing the air in the chamber, it does not capture a true aver-age velocity.A sidewall grille blows air out horizontally and tends to hit the velocity grid higher in some sec-tions than others. For example, some sections could get zero or negative flows. The grid equaliz-es the pressure but doesn’t average it. This gives it higher, false velocity readings.By Brian SharkeyTECHNICALTAB Instrument Mistakes You Should AvoidA technician uses a capture hood on a sidewall grille. This method is not the most accurate way of measuring velocity from a sidewall grille.22 FEBRUARY 2020HIGH-PERFORMANCE HVAC TODAYtraversed individual inlets and discov-ered the capture hood read 7% to 15% lower than the traverse. This varied by grille type and quantity but was con-sistently low. We learned instrument mistake #2: Capture hoods read lower airflow on exhaust and return inlets. Why?Most capture hoods are designed for supply airflow to travel about 36” be-fore it hits the velocity grid. This allows the airflow to even out before the grid, giving an accurate measurement. But exhaust and return airflow has a short-er distance from the hood base before the air hits the velocity grid.To overcome the low airflow read-ings on our exhaust system, we took traverses of the different types of ex-haust grilles and came up with a field derived Ak. This Ak was multiplied with the hood readings to give an ac-curate measurement.Not only did we get correct data for the job, but demonstrated that some problems are not always the mechani-cal contractor’s fault.INSTRUMENT MISTAKE 3: Properly Recording Negative Velocity Readings in a TraverseI teach new technicians to traverse by looking for a straight run of duct, lo-cated three quarters of the way down-stream of the last transition. But in the field, technicians often find these conditions are not always available. Sometimes you have to take the tra-verse in a less-than-ideal location.Traverse points will mostly give you positive readings, but negative read-ings do occur. These readings typically do not indicate negative airflow, but a circular air motion pattern in the duct, similar to an eddy in a river or stream.The flow is circulating and not tru-ly moving in a negative direction. It is common practice to record these readings as zero, not a negative num-ber. When set on pitot tube mode, several meters will record these neg-ative readings as zero. This gives an accurate average velocity.But as every new technician learns, by using the wrong instrument on a traverse, they can run into trouble.For example, I was once onsite with a tech who was having trouble finding a straight run of duct for a traverse. We found a workable section, and he drilled the holes. Then he took read-ings with an airfoil, thinking it would be the same as his pitot tube. Instead, he learned instrument mistake #3.With his meter connected to an air-foil, the negative readings were not stored as zero fpm. Instead, the meter records and uses the negative reading as part of averaging velocity. This cal-culates a lower airflow than the fan is actually moving.To correct this, remove the negative velocity readings from the average and replace them with zero when using an airfoil over the pitot tube. This provides an accurate reading, despite not having the best run of duct for a traverse.INSTRUMENT MISTAKE 4: Using Thermal Hot Wire Anemometer for Traverse Without Accounting for Negative ReadingsOn another occasion, I was out with one of our veteran technicians who was having trouble finding a straight run of duct for a traverse. He drilled holes in the best location possible and gathered his readings using a thermal hot wire.Knowing there would be negative To properly read sidewall grilles, techs should traverse one sidewall grille and obtain a field derived Ak fac-tor (ncilink.com/AKfactor). Once they have the Ak, they use a rotating vane anemometer (RVA) to determine the airflow per grille.INSTRUMENT MISTAKE 2: Using Capture Hoods to Measure Return and Exhaust GrillesI had two new techs with me on a job gathering return and exhaust read-ings. At lunch we looked at the read-ings and realized every fan was 10% to 20% low.One tech suggested the mechanical contractor hadn’t sealed the return or exhaust duct properly and we were dealing with leaky ductwork. It was a good assumption, and one I’d made early in my career. But I suggested we look further.I instructed them to traverse the fan for total airflow, then compare it to the capture hood readings. We eventually TECHNICALAn Airadigm Solutions technician uses an RVA to measure a sidewall grille. Using an RVA on this type of grille will give you the most accurate reading. FEBRUARY 2020 23HVACTODAY.COMto avoid using this unless you have a measurement location in a straight run of duct that is 7.5 duct diameters downstream and three duct diameters upstream from turns or transitions. INSTRUMENT MISTAKE 5: Coil Face Velocity Measurements vs Traverse AirflowSometimes there just isn’t a way to take a duct traverse, but you still need to determine total airflow on an air handling unit. What do you do?I was onsite at a manufacturing plant in Dallas with several units where a duct traverse location was not avail-able. I instructed my trainee to take a velocity measurement at the coil in-let inside the unit to determine to-tal cfm. We discovered that airflow readings, I asked him how he would account for those in his final measure-ment. He said there were no negative readings, and I introduced him to in-strument mistake #4.He was correct that his instrument doesn’t show negative readings. But that doesn’t mean there are no nega-tive readings. The hot wire anemom-eter does not measure directionally. The numbers displayed, whether posi-tive or negative, are displayed and av-eraged as positive. This will calculate a higher cfm than what your fan is actu-ally moving.The hot wire anemometer is anoth-er instrument used to perform a tra-verse. The probe expands and retracts to fit in a small carrying case, which is ideal to travel with. However it is best An Airadigm Solutions technician uses a hot wire to take a traverse in a mechanical room. This tool does not read negative numbers which could make your reading inaccurate.24 FEBRUARY 2020HIGH-PERFORMANCE HVAC TODAYthe area abruptly, the velocity grid picks up a higher velocity in fpm and thus gives higher velocity measure-ments.After looking at months of data, I discovered the 16% higher readings we saw at the manufacturing plant were the same across nearly all our proj-ects. The best way to correct for this is to multiply your results by the re-maining 84%. That will give you read-ings that are closer if you were able to traverse. A word of caution: if your veloci-ty falls below 300 fpm, or your mea-surement is taken on the leaving side of a coil, don’t use the 84% multiplier. The vena contracta effect is no lon-ger a factor, and your readings with-out the multiplier should be accurate. across the coil face was consistent-ly 16% higher than the air-handling units we traversed.We did not know if this was a proj-ect-specific issue or something com-mon to all units. So, we compared coil face and traverse readings on a variety of projects with a wide range of units.This is where we discovered instru-ment mistake #5: coil face velocity measurements read 16% higher than the traversed airflow. I believe the reason for this is Vena Contracta (ncilink.com/VenaContracta), an effect that causes airflow to speed up right before the area reduces.Here’s how this works: Air velocity speeds up just as it enters the fins of the coil (the point of maximum veloc-ity at the smallest area). By reducing TECHNICALBrian Sharkey is the chief training officer for Airadigm Solutions, headquartered in Auburn, NH. His primary focus is on the technical on-boarding and develop-ment of Airadigm Solutions’ TAB Technicians nationwide. He has worked in the field of Test and Balance and Commissioning for more than 25 years. Sharkey is NEBB Certified, LEED Certified, and NBC certified.Vena contracta is an effect that causes airflow to speed up directly before the duct area reduces.FEBRUARY 2020 25HVACTODAY.COMIf you do all the right things that are recom-mended by the industry, are you still endanger-ing your customers? The answer is a definite maybe and that is not good enough.Many years ago, I got in-volved in a lawsuit where a couple bought a new boiler for their home and wound up becoming injured due to venting issues that led to carbon monoxide poi-soning. This is a frustrating story, but one that can be resolved without lawyers if contractors keep their field teams trained and educated on the combustion process.In this scenario, a couple was happy to purchase and have installed into their home a new higher ef-ficiency boiler. Their HVAC contractor was care-ful to follow all the manufacturer’s instructions. They followed procedures and obtained the ap-propriate permit and the job was inspected when it was finished. All is good. Not quite!COSTLY CALL-BACKJust a few days after the boiler was installed, the homeowner found water running down the flue and across the basement floor and laundry room. Guess what? That customer was not hap-py! They called the contractor back. He did addi-tional research and was told he should have used a flue liner because the chimney had a tile lining and the flue gases couldn’t heat it up. So now this contractor, at his own cost, installs a flue liner. Guess what? That solved the water-on-the-floor problem. Several months later, the contractor gets an-other call from the homeowners. They tell him something on the boiler smells like it’s burning and the boiler is no longer working. The contrac-tor returns to the home and finds the wiring melt-ed because the flames had been rolling out. Upon further inspection he finds the flue liner was to-tally corroded and collapsed. He was certainly lucky that was all that happened. GETTING HELPThe contractor consulted with the boiler sup-plier as well as the manufacturer. They recom-mended venting the boiler out of the basement window with a power venter because they felt the flue was just bad. THE MOST IMPORTANT THING IS TO GET TO THE TRUTH OF THE CAUSE AND EFFECT, THEN CORRECT THAT SITUATION.Venting Your Frustrations or Frustrating Your Venting?By Jim DavisTECHNICAL26 FEBRUARY 2020HIGH-PERFORMANCE HVAC TODAYNO FINGER-POINTING!To me, it isn’t about who is or isn’t guilty. The most important thing is to get to the truth of the cause and ef-fect, then correct that situation. In that way, I can protect the victim. The manufacturer’s lawyer was present and was surprised when I didn’t blame the equipment. Did the contractor do anything wrong? That depends on how you de-fine wrong. Did he follow industry standards and manufacturers recom-mendations? Yes! However, there is one thing that is not an industry stan-dard that should be, and that is to ver-ify the equipment is operating safely. There are, however, laws that state contractors are not allowed to endan-ger people. If found guilty of endan-germent, that could put a contractor out of business. The contractor in this case settled out of court as most do in these types of cases. THE PROBLEM(S) …In this scenario, the new copper-fin boiler with a drafthood was much more efficient than the original cast iron boiler and therefore had a much lower flue gas temperature. Above the drafthood, after dilution air, the flue gas temperature was less than 220 degrees. By the time it made it to the flue cap, the gasses were be-low the dew point temperature and condensed. I knew this because of previous ex-perience with this type of boiler. This boiler would be a problem un-less modifications were made. Adding a flue liner rarely stops equipment from condensing but it does prevent water from running across the floor. Think about it: in this case, it only took two months for the acidic mois-ture that condensed out of the flue gases to destroy the aluminized steel liner causing it to collapse. Frankly, it was lucky some wires melted and shut off the boiler. Next comes the addition of a power venter. What could go wrong?A drafthood isolates equipment from the flue. It allows the draft in the flue to draw dilution air from the room instead of the equipment. By defini-tion, a drafthood only works safely if the dilution air is a maximum of 50%. Adding a power venter above a draft-hood increases dilution air up to 80%. The flue can only hold 50% dilution air and 50% flue gas. If there is 80% di-lution air, there is only room for 20% flue gas. That means around 30% of flue gas goes into the house.Bad things happen when vent fans are installed on top of drafthood equip-ment. If the drafthood is left open, someone will be injured, or the equip-ment will be destroyed. When I worked for a supplier of draft fans, I made sure my customers understood how to prop-erly install them and where. Although it didn’t involve a court case, one of the Field Experiences in the NCI CO/Combustion Class discusses a water heater with a fan in the flue. For the record I have found 100% of these installations unsafe. Scary!! So the contractor installed a pow-er venter per everyone’s instructions, vented the boiler through the window, and felt he had done the best he could. Many of us who try to do the right things often feel that by following ex-perts’ instructions, we’re off the hook as far as liability is concerned. Well, if someone tells you to do a backflip off a diving board, isn’t it your responsibility to check and make sure there is water in the pool? The difference is that when you take instructions from a diving instruc-tor, odds are the instructor has really done what he or she is asking you to do. What are the odds that the experts at the distributor have worked in the field as HVAC technicians?Less than a week after the contrac-tor re-installed the boiler and power vented it through the basement win-dow, the lady of the house ended up in the hospital with CO poisoning. Here comes the lawsuit. The con-tractor’s defense is that he did every-thing he was told, and the boiler was at fault. The boiler manufacturer claims there is nothing wrong with the boiler. TELLING THE TRUTHIf all the above isn’t frustrating enough, now the contractor, home-owner, and manufacturer are em-broiled in a legal action where the only winners are the lawyers. I be-came involved in this mess when the homeowner’s lawyer was referred to me as a knowledgeable and experi-enced witness. My main concern any time there is any incident of this nature, is to deter-mine whether the actual problem was discovered and eliminated to prevent a future incident. TECHNICALJim Davis is a 49-year veteran of the HVAC industry. In 1978 he became involved in dis-tributing digital combustion analyzers and found a giant lack of education on how to interpret and apply the information they collected. He’s spent thousands of hours addressing the real issues and problems occurring in the field. FEBRUARY 2020 27HVACTODAY.COMPHOTO OF THE MONTH“Find the Gas Valve” — Eric Kent, Same Day Heating and Air, Salt Lake City, UT In this game of hide-and-seek, a technician is dispatched to a home having an air conditioning issue and found the customer’s furnace in this condition. The funny thing is, the customer is an engineer!!Service Manager Eric Kent from Same Day Heating and Air of Salt Lake City, UT is the February 2020 winner of our Photo-of-the-Month contest, in the What-The-Heck category, as voted on by the subscribers to the High-Performance HVAC Today magazine (hvactoday.com) and visitors to the website. He will receive a $50 gift card.You can too – submissions are always welcome. If you’d like to submit a photo for consideration in our Photo-of-the-Month contest, go to ncilink.com/POMSubmit and fill out the information as requested.THE MARCH 2020 CONTEST OPENS ON FEBRUARY 10, 2020. That gives you plenty of time to submit something in any of our three categories: The Good, The Bad, WTH (What the heck).28 FEBRUARY 2020HIGH-PERFORMANCE HVAC TODAYtrations, you can also use them to cover some other fees.For example, NCI members can cover their golf fees with NCI Bucks. The cost is $260 per golfer which includes fees, lunch, and your cart. If you plan on rent-ing clubs, you should call early to reserve them while they last.You can also use your Bucks to help pay for both pre- and post-convention NCI classes (Go to ncilink.com/Summit-2020Pre-Post for more information). However, classes being held by Goodman and R.E. Michel are not covered by Bucks.The other special class hosted by Women in HVACR is free to all attendees.So what are you waiting for? Register today at ncilink.com/Summit2020Reg.Power Up with the February Power PackYour February 2020 PowerPack is now online exclusively for NCI Members. Every month we hand-pick several digi-tal tools especially for High-Performance contractors like you to help you on your journey towards success. So get ready and power up with this month’s downloads: ❤ Value and Comfort Pre-Season Performance Air Conditioning Tune-Up Flyer (Download) ❤ Fundamentals of Fan Airflow (Online Training) ❤Cooling Test-in Report (Download) ❤ Static Pressure Test Diagram (Download).Be sure to share the February Power Pack with your entire team! Get started today: ncilink.com/PwrPak.NCI’s Newest Partner:Hire DimensionsNational Comfort Institute is pleased to announce the latest addition to our TIPP (Training Incentive Partner Pro-gram) offerings for members. Please join us in welcoming Hire Dimensions – an online soup-to-nuts recruiting engine. Hire Dimensions has more than 25 years of industry experience mostly working with and helping HVAC contrac-tors manage their onboarding, hiring, and screening challenges.By using Hire Dimensions through the NCI website, you can earn NCI bucks which can be used to help pay for any NCI training, including things like regis-tration for the annual NCI High-Perfor-mance HVAC Summit each year.If you have any questions about Hire Dimensions or how to use the TIPP bene-fits, be sure to call (800) 633-7058 and talk to your customer care representative.Ladies and gentlemen, the National Comfort Institute (NCI) 2020 High-Perfor-mance Summit is less than two months away. If you haven’t already done so, now is the time to register and book your rooms at the fabulous We-Ko-Pa Hotel in Scottsdale, AZ. The event takes place from April 5th to 9th.For complete details on what is planned for this year’s event, please check out the Summit brochure on page 13 of this issue.In a nutshell, Summit will focus on how you, as a company and team lead-er, should always be coaching for suc-cess. Summit is open to all HVAC pro-fessionals. It is THE gathering place for like-minded people to learn from and share knowledge with fellow High-Per-formance professionals.This year Summit consists of four days of special events that include workshops led by 9 speakers, a trade show with 25 vendors, our popular ‘Idea Session’, the Partner’s Reception and Trade Show, and our Annual Awards Banquet.Plus, Summit 2020 will see the return of the golf outing at the world-famous We-Ko-Pa Resort golf course.USE YOUR NCI BUCKSBesides being able to use your banked NCI Bucks to cover the cost of your regis-NCI MEMBER UPDATEFEBRUARY 2020 29HVACTODAY.COMHVAC SMART MARTAdvertiser IndexHIGH-PERFORMANCEHVAC TODAYHVAC TODAY TMAD INDEXArzel Zoning Technology, Inc. | www.arzelzoning.com ......................................................23Baker Distributing Company | www.BakerDist.com ........................................................... 24Dwyer Instruments, Inc. | www.dwyer-inst.com .................................................................... 2Goodman Manufacturing | www.GoodmanMfg.com ..........................................................4Lazco Corp. | www.LazcoCorp.com ...............................................................................................9 R.E. Michel Company | www.REMichel.com ...........................................................................10The New Flat Rate | www.TheNewFlatRate.com ..................................................................29 To Your Success | ToYourSuccess.com .......................................................................................29TSI, Inc. | www.TSI.com/comfort .................................................................................................. 6United Refrigeration Inc. | www.uri.com ..................................................................................27To 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 SmithEmail us at contactus@hvactoday.com with your comments and questions.Next >