Residential HVAC System Design Crosswalk to NATE Competencies and Tasks The following North American Technical Excellence (NATE) competencies and tasks are covered in this publication. These competencies and tasks have been taken from a compilation of all of NATE s KATES related to HVAC system design. Only the covered competencies and tasks are listed. The first column identifies the competency or task by name. The second column identifies the exact location in this MAVCC publication where that competency or task is covered. Customer survey Weather Data: Building Orientation: Building Setting Options: On slab construction Crawlspace Partial basement (cellar) Full basement Take Offs Blueprint or Actual Site Review: Construction of walls Area of walls Insulation of walls Number of windows (fenestration) Area of windows (fenestration) Construction of windows (fenestration) Orientation of windows (fenestration) Shading of windows (fenestration) Unit 1, Objective 3 Comfort envelope Unit 3, Objective 7 Gathering heat load information Unit 3, Objective 12 Calculating requirements for solar gains through glass materials Unit 4, Objective 4 Air distribution system selection favors Unit 4, Objective 4 Air distribution system selection favors Unit 4, Objective 4 Air distribution system selection favors Unit 4, Objective 4 Air distribution system selection favors Unit 3, Objective 7 Factors affecting air distribution design Unit 3, Objective 9 Calculating requirements for conduction loads through walls Unit 3, Objective 9 Calculating requirements for conduction loads through walls Unit 3, Objective 9 Calculating requirements for conduction loads through walls Unit 3, Objective 12 Calculating requirements for solar gains through glass materials Unit 3, Objective 12 Calculating requirements for solar gains through glass materials Unit 3, Objective 12 Calculating requirements for solar gains through glass materials Unit 3, Objective 12 Calculating requirements for solar gains through glass materials Unit 3, Objective 12 Calculating requirements for solar gains through glass materials xxvii
Construction, area, and insulation of floors Construction, area, and insulation of ceilings Construction, area, and insulation of roof Construction, area, and thermal effectiveness of skylights Developing a good system design plan Zoning Single Zone: Multiple Zones: Infiltration Air Changes Per Hour: Equal exchange requirements Heat gain/loss per CFM Latent loss/gain per CFM Occupancy Standards: Code requirements per occupancy Ventilation Internal Loads: Human occupancy, equipment loads Unit 3, Objective 10 Calculating requirements for conduction loads through floors Unit 3, Objective 11 Calculating requirements for conduction loads through ceilings Unit 3, Objective 11 Calculating requirements for conduction loads through ceilings Unit 3, Objective 12 Calculating requirements for solar gains through glass materials Unit 4, Objective 7 Factors affecting air distribution system design Unit 4, Assignment Sheet 5 Design an air distribution system Unit 4, Objective 4 Air distribution system selection factors Unit 2, Job Sheet 1 Determine the relative humidity of a conditioned space Unit 4, Objective 4 Air distribution system selection factors Unit 3, Objective 13 Calculating requirements for infiltration and ventilation loads Unit 8, Objective 2 Indoor air quality overview Unit 8, Objective 3 Residential indoor air quality management Unit 2, Objective 7 Charting the changes in a sample of air Unit 2, Assignment Sheet 2 Use the sensible heat to calculate the output in BTU s of a heating system Unit 2, Objective 10 Total heat Unit 4, Objective 4 Air distribution system selection factors Unit 3, Objective 4 Types of heat loads xxviii
Heat Loss Total: Sensible: Latent: Heat Gain Total: Sensible: Latent: Duct Loads Gain: Total/Sensible/Latent Infiltration Loss: Total/Sensible/Latent Infiltration Unit 2, Objective 10 Total heat Unit 2, Objective 14 Using the total heat Unit 1, Objective 10 Specific heat Unit 1, Assignment Sheet 3 Calculate the amount of sensible heat being taken out of the air by an air conditioner Unit 2, Objective 8 The sensible heat Unit 2, Objective 12 Sensible heat versus latent heat Unit 2, Objective 10 Total Heat Unit 2, Objective 12 Sensible heat versus latent heat Unit 2, Objective 10 Total heat Unit 2, Objective 14 Using the total heat Unit 2, Objective 8 The sensible heat Unit 2, Objective 12 Sensible heat versus latent heat Unit 2, Objective 10 Total Heat Unit 2, Objective 12 Sensible heat versus latent heat Unit 3, Objective 4 Types of heat loads Unit 3, Objective 5 Heat losses and gains Unit 3, Objective 14 Calculating requirements for duct and piping loads Unit 3, Objective 4 Types of heat loads Unit 3, Objective 13 Calculating requirements for infiltration and ventilation loads Unit 3, Objective 4 Types of heat loads Unit 3, Objective 5 Heat losses and gains Unit 3, Objective 14 Calculating requirements for duct and piping loads Unit 3, Objective 4 Types of heat loads Unit 3, Objective 13 Calculating requirements for infiltration and ventilation loads xxix
Duct Design Loss: Efficiency impact Comfort impact Improper duct design impact Improper duct installation impact Improper duct location impact Design Considerations Comfort Temperature: Designing for capacity Using industry standards Humidity: Role of humidity in comfort Using industry standards Humidity control related to cooling equipment size Unit 4, Objective 7 Factors affecting air distribution system design Unit 5, Objective 2 Duct locations Unit 5, Objective 3 Aerodynamic efficiency of Unit 4, Objective 2 Air distribution system design Unit 4, Objective 2 Air distribution system design Unit 4, Objective 7 Factors affecting air distribution system design Unit 4, Objective 12 Return air duct design Unit 5, Objective 4 Conduction losses and gains of Unit 4, Objective 2 Air distribution system design Unit 4, Objective 12 Return air duct design Unit 5, Objective 4 Conduction losses and gains of Unit 2, Objective 13 Using the capacity Unit 4, Objective 2 Air distribution system design Unit 1, Objective 3 Comfort envelope Unit 1, Objective 6 Conditioning the air Unit 1, Objective 12 Density of moist air Unit 1, Objective 14 Relative humidity Unit 8, Objective 9 Advantages of maintaining proper humidity in a residence Unit 4, Objective 2 Air distribution system design Unit 2, Job Sheet 1 Determine the relative humidity of a conditioned space Unit 2, Job Sheet 2 Determine the relative humidity of the air inside a duct xxx
Indoor Air Quality: Ventilation: total comfort Air cleaning for comfort Industry standards for air quality Outside air Filter ratings (MERV) related system efficiency Filter effect on system efficiency related to static during load calculation Sound Level: Equipment location considerations Duct systems Zoning: Single/Multi- zones Design Considerations Residential Air Balancing: Duct sizing Unit 8, Objective 3 Residential indoor air quality management Unit 8, Objective 5 Measuring the efficiency of HVAC filters Unit 1, Objective 6 Conditioning the air Unit 8, Objective 2 Indoor air quality overview Unit 8, Objective 5 Measuring the efficiency of HVAC filters Unit 8, Objective 6 Efficiency of particle removing filters Unit 8, Objective 5 Measuring the efficiency of HVAC filters Unit 4, Objective 4 Air distribution selection factors Unit 4, Objective 4 Air distribution selection factors Unit 4, Objective 4 Air distribution selection factors Unit 4, all Objectives Unit 4, Assignment Sheet 1 Determine the effective length of selected duct runs Unit 4, Assignment Sheet 2 Determine the friction rate design value to be used for sizing for a specified system Unit 4, Assignment Sheet 3 Determine duct sizes using a friction chart and ACCCA manual D duct sizing worksheet Unit 4, Assignment Sheet 4 Determine duct sizes using a duct calculator Unit 4, Assignment Sheet 5 Design an air distribution system xxxi
Design Considerations Components Impact of Diffusers, Grilles, and Registers: Selecting Diffusers, Grilles, and Registers: Ducts and Fittings: Specifying physical dimensions Design Considerations Incorrect Load Consequences of under/over-sizing Industry Standards Equipment Standards: Introduction to industry standards System Standards: ASHRAE standards SMACNA standards ACCA standards Unit 4, Objective 13 Air control devices Unit 4, Objective 14 Air control device selection factors Unit 4, Assignment Sheet 5 Design an air distribution system Unit 4, Objective 13 Air control devices Unit 4, Objective 14 Air control device selection factors Unit 4, Assignment Sheet 5 Design an air distribution system Unit 4, Objective 7 Factors affecting air distribution system design Unit 4, Assignment Sheet 1 Determine the effective length of selected duct runs Unit 3, Objective 6 Standards of heat load procedures Unit 9, Objective 2 HVAC quality installation specifications Unit 9, Objective 5 Efficiency ratings for heating equipment Unit 9, Objective 6 Efficiency ratings for cooling equipment Unit 9, Objective 7 Efficiency ratings for heat pump equipment Unit 8, Objective 5 Measuring the efficiency of HVAC filters Unit 6, Objective 5 Installing sheet metal Unit 9, Objective 2 HVAC quality installation specifications Unit 9, Objective 3 Residential HVAC standards xxxii
Airflow Measurements Introduction to Airflow Measurements: Introduction to airflow Static Tools: Using manufacturer s airflow charts/tables Airflow Velocity Measurements: Introduction to airflow velocity Pitot tube and manometer in measuring static Discharge velocity equipment Static drop across evaporator coil Velometer: electronic and mechanical Anemometer Airflow and Velocity Airflow Pressure Measurements: Overview of static measurements Inclined manometer Unit 4, Objective 5 Airflow through an air distribution system Unit 4, Objective 6 Velocity, CFM, and static Unit 4, Job Sheet 1 Determine static drop across an evaporator coil Unit 2, Objective 8 The sensible heat Unit 2, Job Sheet 2 Determine the relative humidity of the air inside a duct Unit 4, Job Sheet 2 Determine the CFM being delivered by a selected forced air system Unit 4, Job Sheet 1 Determine static drop across an evaporator coil Unit 4, Job Sheet 2 Determine the CFM being delivered by a selected forced air system Unit 4, Objective 8 Factors to consider in the distribution of conditioned air Unit 4, Job Sheet 2 Determine the CFM being delivered by a selected forced air system Unit 4, Job Sheet 1 Determine static drop across an evaporator coil xxxiii
Diaphragm type differential gauge U-tube manometer Electronic manometer/ measurement Gauge/Meter calibration Static Air measurement terminology Velocity measurement Air Volume Measurements: Introduction to volume Airflow hood Formulae for determining CFM of air Unit 4, Job Sheet 1 Determine static drop across an evaporator coil Unit 4, Job Sheet 1 Determine static drop across an evaporator coil Unit 4, Job Sheet 1 Determine static drop across an evaporator coil Unit 4, Job Sheet 1 Determine static drop across an evaporator coil Unit 4, Job Sheet 1 Determine static drop across an evaporator coil Throughout Unit 1, Objective 9 Specific volume Unit 1, Assignment Sheet 1 Calculate the weight of the air in a residence and the amount of heat required to warm the house Unit 2, Objective 6 Plotting the changes in the air on a psychrometric chart Unit 2, Objective 7 Charting the changes in a sample of air Unit 1, Objective 11 Specific density Unit 1, Assignment Sheet 2 Calculate the amount of heat being transferred into the house by a heating system Unit 2, Objective 9 The temperature rise Unit 2, Assignment Sheet 3 Use the temperature rise to calculate the CFM output of an electric furnace air handler for a heat pump system Unit 2, Assignment Sheet 4 Use the temperature rise to calculate the CFM output of a gas furnace xxxiv
Airflow volume: CFM/SCFM Airflow Checks and Design Tools: Using manufacturer s airflow charts and tables Using a duct calculator and design charts Equipment Selection Capacity Design Heating Load: Total load Sensible load Unit 1, Objective 9 Specific volume Unit 4, Objective 15 Friction charts, equivalency tables, and duct calculators Unit 4, Assignment Sheet 2 Determine the friction rate design value to be used for sizing for a specified system Unit 4, Assignment Sheet 3 Determine duct sizes using a friction chart and ACCA manual D duct sizing worksheet Unit 4, Objective 15 Friction charts, equivalency tables, and duct calculators Unit 4, Assignment Sheet 4 Determine duct sizes using a duct calculator Unit 2, Objective 13 Using the capacity Unit 3, Assignment Sheet 1 Locate heat load and structure information on a Manual J8 AE form J1 AE Unit 4, Objective 3 Major steps in air distribution design Unit 9, Assignment Sheet 1 Select suitable heating and cooling equipment for a residence Unit 2, Objective 13 Using the capacity Unit 3, Objective 3 Heat loads and Unit 3, Assignment Sheet 1 Locate heat load and structure information on a Manual J8 AE form J1 AE Unit 4, Objective 3 Major steps in air distribution design Unit 9, Assignment Sheet 1 Select suitable heating and cooling equipment for a residence xxxv
Latent load CFM/FPM requirements Impacts of over-sizing and/or under-sizing Design Cooling Load: Total load Sensible load Latent load CFM/FPM requirements Impact of airflow on humidity removal Unit 2, Objective 13 Using the capacity Unit 3, Assignment Sheet 1 Locate heat load and structure information on a Manual J8 AE form J1 AE Unit 4, Objective 3 Major steps in air distribution design Unit 9, Assignment Sheet 1 Select suitable heating and cooling equipment for a residence Unit 4, Objective 15 Friction charts, equivalency tables, and duct calculators Unit 2, Objective 13 Using the capacity Unit 4, Objective 3 Major steps in air distribution design Unit 2, Objective 13 Using the capacity Unit 4, Objective 3 Major steps in air distribution design Unit 2, Objective 13 Using the capacity Unit 4, Objective 3 Major steps in air distribution design Unit 4, Objective 15 Friction charts, equivalency tables, and duct calculators xxxvi
Impacts of over-sizing and/or under-sizing Design Ventilation Load: Impact of airflow on humidity removal Impacts of over-sizing and/or under-sizing Efficiency System Efficiency: Define inside/outside conditioned space Heating Efficiency: Gas furnace/boiler: Annual Fuel Utilization Efficiency (AFUE) Efficiency gains with condensing furnaces vs. 80% Discussion of reduced comfort/efficiency of over-sized heating systems Cooling Efficiency: Seasonal Energy Efficiency Ration (SEER) Energy Efficiency Ratio (EER) Unit 3, Objective 13 Calculating requirements for infiltration and ventilation loads Unit 5, Objective 4 Conductive losses and gains of Unit 9, Objective 5 Efficiency ratings for heating equipment Unit 9, Objective 5 Efficiency ratings for heating equipment Unit 9, Objective 6 Efficiency ratings for cooling equipment Unit 9, Objective 6 Efficiency ratings for cooling equipment xxxvii
Air Distribution Systems and Components Heat Transfer and the Heating/Cooling Cycle: Psychrometrics Duct Systems Basic Duct Systems: Overview of duct systems Duct configuration: Extended plenum, reducing extended plenum, perimeter radial, perimeter loop, and overhead radial Unit 2, Objective 3 The psychrometric chart Unit 2, Objective 4 Reading the psychrometric chart Unit 2, Objective 5 Locating plot points and their values on the psychrometric chart Unit 2, Objective 6 Plotting the changes in air on the psychrometric chart Unit 2, Focus Assignment Locate psychrometric charts Unit 2, Assignment Sheet 1 Plot air in and air out points and the values in the process on a psychrometric chart Unit 2, Assignment Sheet 5 Calculate the total heat being transferred by a cooling system Unit 2, Assignment Sheet 6 Plot the process line, find the sensible heat ratio, and calculate how much of the total heat being transferred by a cooling system is sensible heat andhow much is latent heat Unit 2, Job Sheet 1 Determine the relative humidity of a conditioned space Unit 2, Job Sheet 2 Determine the relative humidity of the air inside a duct Unit 4, Objective 9 Types of supply duct systems Unit 5, Objective 1 Duct composition Unit 5, Objective 2 Duct locations Unit 5, Objective 3 Aerodynamic efficiency of Unit 5, Objective 7 Installation costs of Unit 4, Objective 9 Types of supply duct systems xxxviii
Duct Locations: Attic, basement, crawlspace, slab, roof, chases Duct Materials: Define/Recognize duct board Define/Recognize metal duct Define/Recognize flexible duct Define/Recognize PVC pipe Insulating material Fitting Nomenclature: Define/Recognize plenum, transition, 90 and 45 degrees, round duct, and rectangle duct Return configurations Sheet metal duct joints: s and drive, snaplock, etc. Dampers, Grilles, Registers, and Diffusers: Types and uses Unit 4, Objective 9 Types of supply duct systems Unit 4, Objective 11 Advantages and disadvantages for locations of supply air outlets Unit 5, Objective 1 Duct composition Unit 5, Objective 2 Duct locations Unit 6, Objective 3 Metal and PVC duct locations Unit 7, Objective 2 Fiberglass duct locations Unit 7, Objective 4 Fabricating duct board system components Unit 6, Objective 2 Metal and PVC duct applications Unit 7, Objective 6 Installing flex Unit 6, Objective 2 Metal and PVC duct applications Unit 6, Objective 7 Insulating sheet metal Unit 6, Objective 8 Insulation used on the outside of sheet metal Unit 6, Objective 9 Insulation used on the inside of sheet metal Unit 4, Objective 9 Types of supply duct systems Unit 4, Objective 12 Return air duct design Unit 6, Objective 4 Assembling sheet metal Unit 6, Objective 5 Installing sheet metal Unit 4, Objective 13 Air control devices Unit 4, Objective 14 Air control device selection factors xxxix
Filtration Systems: Media type filters Humidifiers: Fundamentals of operation Types Installation support and location Installation Duct Fabrication Duct Fabrication Equipment: Ductboard tools: 90 V-groove Flex tools: tensioning strap tools, knives, etc. Metal tools: metal snips, sheers, benders, breaks, hand formers, calipers, rulers, stapler, etc. Fabrication Techniques For Metal Duct: Making seams: Pittsburgh and snap lock Making transverse joints: drive clips, reinforced drive clips, s clip, and standing s clip Crimping round pipe Unit 8, Objective 6 Efficiency of particle removing filters Unit 8, Job Sheet 1 Clean or replace filters in a residential HVAC system Unit 8, Objective 11 Operation of a typical humidifier with a force air furnace Unit 8, Objective 11 Operation of a typical humidifier with a force air furnace Unit 8, Objective 11 Operation of a typical humidifier with a force air furnace Unit 8, Job Sheet 2 Install a humidifier with low voltage controls Unit 7, Job Sheet 1 Fabricate a one-piece straight duct board section using the V-groove method Unit 6, Job Sheet 4 - Install in or under a concrete slab Unit 6, Objective 5 Installing sheet metal seal sheet metal Unit 6, Job Sheet 2 Install duct wrap Unit 6, Job Sheet 3 Install duct liner Unit 6, Objective 4 Assembling sheet metal seal sheet metal Unit 6, Objective 5 Installing sheet metal Unit 6, Objective 6 Sealing sheet metal Unit 6, Objective 5 Installing sheet metal seal sheet metal xl
Fabrication Techniques for Duct Board: Layout of duct fitting Groove cutting Approved type of joint tape Use of joint tape UL 181 Duct Installation Field Construction/Installation: Duct board installation techniques Duct of alternate materials Installing Metal Duct: Assembly methods for rectangular duct Unit 7, Objective 4 Fabricating duct board system components Unit 7, Job Sheet 1 Fabricate a one-piece straight duct board section using the V-groove method Unit 7, Job Sheet 2 Fabricate an end cap to fit a one-piece straight duct board section Unit 7, Objective 4 Fabricating duct board system components Unit 7, Job Sheet 1 Fabricate a one-piece straight duct board section using the V-groove method Unit 7, Job Sheet 2 Fabricate an end cap to fit a one-piece straight duct board section Unit 6, Objective 6 Sealing metal Unit 7, Objective 4 Fabricating duct board system components Unit 7, Objective 5 Installing fiberglass duct board components Unit 7, Objective 4 Fabricating duct board system components Unit 7, Objective 5 Installing fiberglass duct board components Unit 7, Job Sheet 1 Fabricate a one-piece straight duct board section using the V-groove method Unit 7, Job Sheet 2 Fabricate an end cap to fit a one-piece straight duct board section Unit 6, Objective 6 Sealing metal Unit 7, Objective 5 Installing fiberglass duct board components Unit 7, Objective 5 Installing fiberglass duct board components Unit 5, Objective 1 Duct composition Unit 6, Objective 4 Assembling sheet metal seal sheet metal xli
Installation technique: rectangular metal Assembly methods for round duct Installation technique: round metal Hanging ductwork Sealing metal duct Insulation: internal and external, vapor barriers Installing Flexible Duct: Assembly methods: appropriate length Flexible duct joints Hanging flexible duct Installation technique Sealing flexible duct Unit 6, Objective 5 Installing sheet metal seal sheet metal Unit 6, Objective 4 Assembling sheet metal seal sheet metal Unit 6, Objective 5 Installing sheet metal seal sheet metal Unit 6, Objective 5 Installing sheet metal seal sheet metal Unit 6, Objective 6 Sealing sheet metal seal sheet metal Unit 6, Objective 7 Insulating sheet metal Unit 6, Objective 8 Insulation used on the outside of sheet metal Unit 6, Objective 9 Insulation used on the inside of sheet metal Unit 6, Job Sheet 2 Install duct wrap Unit 6, Job Sheet 3 Install duct liner Unit 7, Objective 6 Installing flex Unit 7, Job Sheet 3 Install a section of flex duct Unit 7, Objective 6 Installing flex Unit 7, Job Sheet 3 Install a section of flex duct Unit 7, Objective 6 Installing flex Unit 7, Job Sheet 3 Install a section of flex duct Unit 7, Objective 6 Installing flex Unit 7, Job Sheet 3 Install a section of flex duct Unit 7, Objective 6 Installing flex Unit 7, Job Sheet 3 Install a section of flex duct xlii
Installing Duct Board: Assembly methods for duct board: supports Installation technique Sealing duct board Chases Used as Ducts: Indoor Air/Environmental Quality Designing for Acceptable IAQ/IEQ: Understanding ventilation and acceptable IAQ Operating and Maintaining IAQ/IEQ Systems: Filtration systems Unit 7, Objective 4 Fabricating duct board system components Unit 7, Job Sheet 3 Install a section of flex duct Unit 7, Objective 4 Fabricating duct board system components Unit 7, Objective 5 Installing fiberglass duct board components Unit 7, Job Sheet 3 Install a section of flex duct Unit 5, Objective 6 Sealing Unit 7, Objective 5 Installing fiberglass duct board components Unit 4, Objective 5 Airflow through an air distribution system Unit 5, Objective 6 Sealing Unit 8, Objective 2 Indoor air quality (IAQ) overview Unit 8, Objective 3 Residential indoor air quality management Unit 8, Objective 4 Air contaminants that affect humans Unit 8, Objective 5 Measuring the efficiency of HVAC filters Unit 8, Objective 6 Efficiency of particle removing filters Unit 8, Objective 7 Installation and service of HVAC filters Unit 8, Job Sheet 1 Clean or replace filters in a residential HVAC system xliii