hvac instant answers - mcgraw-hill educationbooks.mhprofessional.com/engineering/pdfs/hvac.pdf ·...

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With this handy portable guide along on every job, you’ll know instantly how to… Troubleshoot HVAC problems correctly and efficiently Get calculations right every time with valuable look-up tables Follow succinct, step-by-step procedures for working with ducts… water, steam, and pipes…electricity and wiring…pumps and valves… sensors, actuators and controllers… water and steam distribution systems…chillers…boilers — and much more Benefit from hundreds of savvy money-saving techniques and tips Ensure the safety of facilities personnel and building residents Avoid damage to expensive equipment and systems MORE! EXTRA BONUS: Order online and get FREE shipping and handling! Details Inside… Chapter 1. Introduction and Overview How Buildings Work Chapter 2. Air and Ducts Air Psychrometrics Ducts Air Compressors Chapter 3. Water, Steam, and Pipes Water Steam Pipes and Tubing Iron and Steel Pipes Copper Tubing Plastic Piping Support and Insulation Heat Exchangers Performance of Heat Exchangers Chapter 4. Electricity and Wiring DC Circuits AC Circuits Wye and Delta Circuits Variable Speed Drives Transformers Circuit Breakers and Fuses Electric Switches Wires Power Measurement and Electric Rates Consumption Demand Cost Adjustments and Other Charges Chapter 5. Measurement and Control Temperature Sensors Pneumatic Temperature Sensors Electric Temperature Sensors Humidity Sensors Air Flow Sensors Water Flow Sensors Pressure Sensors Power Sensors Pneumatic Actuators and Controllers Electronic Actuators and Controllers Sensor Noise Rejection and Shielding Control Loops Chapter 6. Pumps and Valves Theory of Operation Centrifugal Pumps Pump and System Curves Positive Displacement Pumps Valves Valve Types Controls Safety Deadheading Cavitation Personnel Safety Valve Disassembly and Repacking Troubleshooting Electric Pump Practical Considerations Pump Bearings Pump Seals Pump Motors Control Valves Glycols Chapter 7. Water Distribution Systems Theory of Operation Two and Four Pipe Systems Parallel, Series, and Variable- Speed Pumping Control Primary/ Secondary Loop Secondary/Tertiary Loop Differential Pressure Control Static Pressure Control Safety Troubleshooting Low Flow in System Water Temperature Not at Setpoint Control Valves Not Working or Too Noisy Reheat Coils Not Working Practical Considerations Piping Pumps and Valves Water Treatment Chapter 8. Chillers Theory of Operation Vapor Compression Cycle Compressors Other Chiller Components Direct Expansion Absorption Cycle Controls Chiller Safeties and Flow Interlocks DX Control Current Limiting Safety Troubleshooting Practical Considerations Staging Multiple Chillers DX Units Noisy Compressors Keep It Clean Keep It Under Control Chapter 9. Air-Cooled Condensers and Cooling Towers Theory of Operation Controls Air-Cooled Condenser Fan Staging Cooling Tower Capacity Control Heat Recovery Safety Troubleshooting Cooling Towers Practical Considerations Maintenance Free Cooling Controls Chapter 10. Thermal Energy Storage Systems Theory of Operation Cooling Storage Heating Storage, Control Cooling Storage Safety, Troubleshooting Practical Considerations Chapter 11. Boilers Theory of Operation Boiler Rating Ignition Controls Boiler Safety Hot Water Reset Safety Boiler Controllers Troubleshooting Practical Considerations Water Treatment Chapter 12. Steam Distribution Systems Theory of Operation Steam Piping and Valves Steam Traps Steam-to-Air Heat Exchangers Steam-to-Water Heat Exchangers Condensate Return Systems Control Steam-to-Air Coils Steam-to-Water Coils Humidification Safety Steam Valves and Traps Troubleshooting Troubleshooting Steam Baseboard Heaters Practical Considerations Chapter 13. Fans and Dampers Theory of Operation Fans Dampers Fire Dampers Face and Bypass Dampers Control Safety Troubleshooting Fan Doesn’t Start or Has Low Flow Damper Does Not Operate Practical Considerations Measuring Air Flow Energy Conservation Chapter 14. Air-Handling Units Theory of Operation Filters Dampers Coils Humidifiers and Dehumidifiers Controls Damper Control Temperature Safety Troubleshooting Mixed Air Temperature (Too Hot or Too Cold) AHU Supply Air Temperature is Not at Setpoint or Varies Too Much Airflow Too Low/Fan Doesn’t Start Practical Considerations Installation Considerations Bearing Lubrication Freeze Protection Chapter 15. Air Distribution Systems Theory of Operation Return Fans, Exhaust Fans, and Relief Fans Run-Around Loops Humidification and Dehumidification Controls Duct Pressure Control Building Warm-Up/Cool-Down Economizer and Night Purging CAV and VAV System Control Safety Troubleshooting Supply Air Flow Rate/Static Pressure Too Low Supply Air Flow Rate/Static Pressure Too High Supply Air Too Cold or Too Hot Supply Air is Too Humid or Too Dry Too Much Noise from Supply Air Duct Practical Considerations Chapter 16. Zone Terminal Systems Theory of Operation Single Duct VAV Boxes Double-Duct Boxes Induction Boxes Diffusers Fan-Coil Units and Radiant Heating Thermostats Control Safety Troubleshooting Zone Too Hot Zone Too Cold Practical Considerations Zone Pressurization Chapter 17. Evaporative Cooling Theory of Operation Controls Safety Troubleshooting Practical Considerations Chemical Treatment and Dirt Build-up Chapter 18. Residential Systems Theory of Operation Heat Pumps Controls Safety Troubleshooting Furnace Cycles Too Much Space is Too Hot or Too Cold Furnace is Too Noisy Practical Considerations Appendix A. Tools for the Technician Appendix B. Using Multimeters Index Your toughest HVAC questions… ANSWERED IN SECONDS! HVAC INSTANT ANSWERS – The indispensable on-the-job problem-solver that covers it all! Order online @ books.mcgraw-hill.com Enter Special Reference Code AKCI208Z (Shipping & Handling are FREE with your online order) 1 Mail the order form attached to the enclosed letter in the postpaid reply envelope. 2 Call toll-free 1-800-2-MCGRAW (1-800-262-4729) 24 hours a day. Please mention code AKCI208Z 3 Fax completed order form to: 1-800-262-4729 4 4 EASY WAYS TO ORDER: 30-DAY MONEY-BACK GUARANTEE! If you are not satisfied with HVAC INSTANT ANSWERS for any reason, return it within 30 days for a full refund – no questions asked! 30-DAY MONEY-BACK GUARANTEE! Your toughest HVAC questions… ANSWERED IN SECONDS!

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With this handy portable guidealong on every job, you’ll knowinstantly how to…

✧ Troubleshoot HVAC problemscorrectly and efficiently

✧ Get calculations right every timewith valuable look-up tables

✧ Follow succinct, step-by-stepprocedures for working with ducts…water, steam, and pipes…electricityand wiring…pumps and valves…sensors, actuators and controllers…water and steam distributionsystems…chillers…boilers — andmuch more

✧ Benefit from hundreds of savvymoney-saving techniques and tips

✧ Ensure the safety of facilitiespersonnel and building residents

✧ Avoid damage to expensiveequipment and systems

✧ MORE!EXTRABONUS:

Order online and getFREE shipping and

handling!

Details Inside…

Chapter 1. Introduction and Overview✧How Buildings Work

Chapter 2. Air and Ducts✧Air ✧Psychrometrics ✧Ducts ✧AirCompressors

Chapter 3. Water, Steam, and Pipes✧Water ✧Steam ✧Pipes and Tubing ✧Ironand Steel Pipes ✧Copper Tubing ✧PlasticPiping ✧Support and Insulation ✧HeatExchangers ✧Performance of HeatExchangers

Chapter 4. Electricity and Wiring✧DC Circuits ✧AC Circuits ✧Wye and DeltaCircuits ✧Variable Speed Drives✧Transformers ✧Circuit Breakers and Fuses✧Electric Switches ✧Wires ✧PowerMeasurement and Electric Rates✧Consumption ✧Demand ✧Cost Adjustmentsand Other Charges

Chapter 5. Measurement and Control✧Temperature Sensors ✧PneumaticTemperature Sensors ✧Electric TemperatureSensors ✧Humidity Sensors ✧Air FlowSensors ✧Water Flow Sensors ✧PressureSensors ✧Power Sensors ✧PneumaticActuators and Controllers ✧ElectronicActuators and Controllers ✧Sensor NoiseRejection and Shielding ✧Control Loops

Chapter 6. Pumps and Valves✧Theory of Operation ✧Centrifugal Pumps✧Pump and System Curves ✧PositiveDisplacement Pumps ✧Valves ✧Valve Types✧Controls ✧Safety ✧Deadheading✧Cavitation ✧Personnel Safety ✧ValveDisassembly and Repacking ✧Troubleshooting✧Electric Pump ✧Practical Considerations✧Pump Bearings ✧Pump Seals ✧PumpMotors ✧Control Valves ✧Glycols

Chapter 7. Water Distribution Systems✧Theory of Operation ✧Two and Four PipeSystems ✧Parallel, Series, and Variable-Speed Pumping ✧Control ✧Primary/Secondary Loop ✧Secondary/Tertiary Loop✧Differential Pressure Control ✧StaticPressure Control ✧Safety ✧Troubleshooting

✧Low Flow in System ✧Water TemperatureNot at Setpoint ✧Control Valves Not Workingor Too Noisy ✧Reheat Coils Not Working✧Practical Considerations ✧Piping ✧Pumpsand Valves ✧Water Treatment

Chapter 8. Chillers✧Theory of Operation ✧Vapor CompressionCycle ✧Compressors ✧Other ChillerComponents ✧Direct Expansion ✧AbsorptionCycle ✧Controls ✧Chiller Safeties and FlowInterlocks ✧DX Control ✧Current Limiting✧Safety ✧Troubleshooting ✧PracticalConsiderations ✧Staging Multiple Chillers✧DX Units ✧Noisy Compressors ✧Keep ItClean ✧Keep It Under Control

Chapter 9. Air-Cooled Condensers andCooling Towers✧Theory of Operation ✧Controls ✧Air-CooledCondenser Fan Staging ✧Cooling TowerCapacity Control ✧Heat Recovery ✧Safety✧Troubleshooting ✧Cooling Towers ✧PracticalConsiderations ✧Maintenance ✧Free Cooling✧Controls

Chapter 10. Thermal Energy StorageSystems✧Theory of Operation ✧Cooling Storage✧Heating Storage, Control ✧Cooling Storage✧Safety, Troubleshooting ✧PracticalConsiderations

Chapter 11. Boilers✧Theory of Operation ✧Boiler Rating ✧Ignition✧Controls ✧Boiler Safety ✧Hot Water Reset✧Safety ✧Boiler Controllers ✧Troubleshooting✧Practical Considerations ✧Water Treatment

Chapter 12. Steam Distribution Systems✧Theory of Operation ✧Steam Piping andValves ✧Steam Traps ✧Steam-to-Air HeatExchangers ✧Steam-to-Water Heat Exchangers✧Condensate Return Systems ✧Control✧Steam-to-Air Coils ✧Steam-to-Water Coils✧Humidification ✧Safety ✧Steam Valves andTraps ✧Troubleshooting ✧TroubleshootingSteam Baseboard Heaters ✧PracticalConsiderations

Chapter 13. Fans and Dampers✧Theory of Operation ✧Fans ✧Dampers✧Fire Dampers ✧Face and Bypass Dampers✧Control ✧Safety ✧Troubleshooting ✧Fan

Doesn’t Start or Has Low Flow ✧DamperDoes Not Operate ✧Practical Considerations✧Measuring Air Flow ✧Energy Conservation

Chapter 14. Air-Handling Units✧Theory of Operation ✧Filters ✧Dampers✧Coils ✧Humidifiers and Dehumidifiers✧Controls ✧Damper Control ✧Temperature✧Safety ✧Troubleshooting ✧Mixed AirTemperature (Too Hot or Too Cold) ✧AHUSupply Air Temperature is Not at Setpoint orVaries Too Much ✧Airflow Too Low/FanDoesn’t Start ✧Practical Considerations✧Installation Considerations ✧BearingLubrication ✧Freeze Protection

Chapter 15. Air Distribution Systems✧Theory of Operation ✧Return Fans, ExhaustFans, and Relief Fans ✧Run-Around Loops✧Humidification and Dehumidification✧Controls ✧Duct Pressure Control ✧BuildingWarm-Up/Cool-Down ✧Economizer and NightPurging ✧CAV and VAV System Control✧Safety ✧Troubleshooting ✧Supply Air FlowRate/Static Pressure Too Low ✧Supply AirFlow Rate/Static Pressure Too High ✧SupplyAir Too Cold or Too Hot ✧Supply Air is TooHumid or Too Dry ✧Too Much Noise fromSupply Air Duct ✧Practical Considerations

Chapter 16. Zone Terminal Systems✧Theory of Operation ✧Single Duct VAVBoxes ✧Double-Duct Boxes ✧Induction Boxes✧Diffusers ✧Fan-Coil Units and RadiantHeating ✧Thermostats ✧Control ✧Safety✧Troubleshooting ✧Zone Too Hot ✧Zone TooCold ✧Practical Considerations ✧ZonePressurization

Chapter 17. Evaporative Cooling✧Theory of Operation ✧Controls ✧Safety✧Troubleshooting ✧Practical Considerations✧Chemical Treatment and Dirt Build-up

Chapter 18. Residential Systems✧Theory of Operation ✧Heat Pumps✧Controls ✧Safety ✧Troubleshooting✧Furnace Cycles Too Much ✧Space is TooHot or Too Cold ✧Furnace is Too Noisy✧Practical Considerations

Appendix A. Tools for the TechnicianAppendix B. Using MultimetersIndex

Your toughest HVAC questions…ANSWERED IN SECONDS!

HVAC INSTANT ANSWERS –The indispensable on-the-job problem-solver that covers it all!

Order online @ books.mcgraw-hill.comEnter Special Reference Code AKCI208Z(Shipping & Handling are FREE with your online order)

1 Mail the order form attachedto the enclosed letter in thepostpaid reply envelope.

2 Call toll-free 1-800-2-MCGRAW(1-800-262-4729) 24 hours a day.Please mention code AKCI208Z

3 Fax completedorder form to:1-800-262-4729

44 EASY WAYS TO ORDER:

30-DAYMONEY-BACKGUARANTEE!

If you are not satisfied with HVAC INSTANT ANSWERS for any reason,return it within 30 days for a full refund – no questions asked!

30-DAYMONEY-BACKGUARANTEE!

Your toughest HVAC questions…ANSWERED IN SECONDS!

✧ Handy portable size (5” x 8”) – for on-the-jobanswers where and when you need them

✧ Formatted to help you quickly find what youneed by category

✧ Tried-and-tested step-by-step instructions

✧ Special boxed material in each section, calledfastfacts, alert you to critical details

✧ Hundreds of crystal-clear photos, illustrations,and always-right calculation tables and checklists

ISBN 007138701-3

HVACinstantanswersHVACinstantanswers

Packed with schematic diagrams, system layouts, flowcharts, and graphics, HVAC Instant Answersis a reliable, convenient, “answers-at-your-fingertips” resource. If you’re just entering the field, it’s agreat learning tool that will quickly and smoothly ease you into on-the-job skill and confidence.

If you’re an experienced HVAC professional, you’ll find it indispensable for its wealth of immediatelyaccessible tables, tips and techniques. This is the place to look for crystal-clear descriptions of com-mon symptoms and problems – and the quickest and best solutions possible.

✧ Understand the mechanics of ductwork

✧ Use the psychrometric charts to design and troubleshootHVAC systems that heat, cool, or humidify the air

✧ Become familiar with all functioning parts of HVACsystems with break-away views, like this one of atypical valve p. 129

✧ Know how to properly mount and support plastic pipingto account for its expansion due to temperature change

✧ Find a simple way to determine how much energy istransferred across air-to-air coils or air-to-water coils

✧ Avoid creating a fire hazard in a residential HVACsystem with the cable tip on p. 70

✧ Identify a problem with HVAC equipment by trackingits electrical efficiency

✧ Design and debug control systems p. 111

✧ Follow safety guidelines to eliminate costly consequences,from expensive equipment repair or replacement tocatastrophic injuries to facilities personnel

✧ Test if a valve is piped backwards (often the causeof water hammer). Directions on p. 195

✧ Recognize features common to the operation of all chillers– knowledge that can eliminate troubleshootingheadaches. See discussion beginning on p. 223

✧ Save a tremendous amount of energy and reduce thewear and tear on the chiller compressor by divertingcooling water to the secondary water distributionsystem p. 244

✧ Find an extensive troubleshooting flowchart for hotwater boilers (it’s on pp. 288-295)

✧ Install steam pressure gauges at several point along thesteam lines – a cheap way to prevent you from making abig, expensive mistake

✧ Ensure your personal safety with lock out/tag outprocedures when working with steam

✧ Get unresponsive damper motors, which fail moreoften than fan motors, working again

✧ Explore practical installation considerations that ensurelong life and proper operation of an air-handling unit

✧ Pick from among several workable strategies tosuppress noise from supply air ducts

✧ Troubleshoot swamp coolers

✧ Follow a few simple rules to ensure safe, properoperation and good readings from a multimeter

Find the HVAC information you need Find the HVAC information you need

HVAC INSTANT ANSWERS TELLS YOU EXACTLY WHAT STEPS TO TAKEWHEN PROBLEMS OCCUR WITH:

• Air distribution systems• Central cooling plants• Compressors• Condensers and cooling towers• Converters• Fans and pumps

• Rooftop units• Water and steam distribution systems• Thermal energy storage systems• Valves and dampers• Water loops• Zones

You get handy lists of tools, specification charts — andjust about everything else you need to get any HVAC jobdone quickly and correctly

Fastfacts in everychapter tell youwhat to do…what to avoid…best bets…bad moves

This “how-to” powerhouseis loaded with schematics.Here’s a Wheatstone bridgecircuit, often used in HVACsensors

Much, much more! SeeBack…

INAFLASH!INAFLASH!