Hvac Stuff

979 views

Published on

A 30,000 foot overview of many of the basics of HVAC systems for property management professionals, created to facilitate their understanding of the issues/processes and support/enhance their engagement with both tenants and engineering professionals.

Hvac Stuff

  1. 1. HVAC Stuff© Three basic premises to hang on to: 1. This is much simpler than it looks2. Heat “falls” naturally from hot to cold 3. Changing state is like gooder than magic . . . Copyright PMFreeman©
  2. 2. HVAC Stuff© Looks complicated, but really a roller coaster mostly is just falling . . .;lkj;lkj;lkj;lkj;lkj Copyright PMFreeman©
  3. 3. HVAC Stuff©Again, it may look complicated, but it isn’t . . .;lkj;lkj;lkj;lkj;lkj Copyright PMFreeman©
  4. 4. HVAC Stuff© Heat moves naturally (falls without help) from warmer things to cooler things . . . ;lkj;lkj;lkj;lkj;lkjSteam rising from the hotdog is an indication ofevaporation occurring Drops of water on the outside of the cup is an indication of condensation occurring. Copyright PMFreeman©
  5. 5. HVAC Stuff©The implications of this evaporation andcondensation “change of state” stuff is prettyamazing . . . This is a huge chunk of our playground . . . Copyright PMFreeman©
  6. 6. HVAC Stuff©(a common approach – but not the only approach)General goal is to take the hot outside cooling tower Once we get rid of the hot, we return cold air water refrigerant water air handler chiller office Copyright PMFreeman©
  7. 7. HVAC Stuff© compressor 100-130 F condenser metering device evaporator Copyright PMFreeman©
  8. 8. Loop 1: Air©The air loop The air iscircles between moved by aoffices and an air fan in theair-handler air handleropen plenum closed duct hot hot open ceiling with exposed duct air handler hot office Copyright PMFreeman©
  9. 9. Loop 1: Air© airWhat components: Why:Filters Clean the airDucts/Plenum Carry the airVents/Diffusers/Returns Direct/Control the flow of the airVAV’s Control the amount of airPIU’s Control the amount and temp of airFans Move the airInsulation Maintain air temp in ducts, etc.Air Handler Coils Transfer the heat from the air to the water-cool/dehumidify the air Copyright PMFreeman©
  10. 10. Loop 2: Water© air handler water Chilled water supply piping Chilled water return pipingWater loop (2) circlesbetween the air handlerand the chiller. The wateris put into motion by a chillerchilled water pump. ->
  11. 11. Loop 2: Water© waterWhat components: Why:Water Carry the heatPiping Carry the waterAir Handler Coils Transfer heat from air to waterInsulation Maintain the water temperatureWater Treatment Keep the water cleanChilled Water Pump Move the waterEvaporator (Chiller) Transfer heat from water to refrigerant Copyright PMFreeman©
  12. 12. Loop 3: Refrigerant© compressorcondenser refrigerant chiller evaporatorThe refrigerant loop remainscontained within the chiller andfollows a four-step process: 1)evaporator, 2) compressor, 3)condenser and 4) expansion chillervalve Copyright PMFreeman©
  13. 13. Loop 3: Refrigerant© compressorcondenser refrigerant evaporatorThe refrigerant loop remainscontained within the chiller andfollows a four-step process: 1)evaporator, 2) compressor, 3)condenser and 4) expansion chillervalve Copyright PMFreeman©
  14. 14. Loop 3: Refrigerant© refrigerant What components: Why: Evaporator Transfer heat from water to refrigerant Compressor Raise refrigerant temperature Condenser Transfer heat from refrigerant to water Expansion Valve Lower refrigerant temperature Purge Clean refrigerant Copyright PMFreeman©
  15. 15. Loop 4: Water©cooling tower water Condenser water supply piping Condenser water return pipingWater loop (4) circlesbetween the chiller andthe cooling tower. Thewater is put into motionby a condenser water chillerpump. -> Copyright PMFreeman©
  16. 16. Loop 4: Water© waterWhat components: Why:Water Carry the heatPiping Carry the waterCondenser Coils Transfer heat from refrigerant to waterInsulation Maintain the water temperatureWater Treatment Keep the water free from contaminantsSand Filter Cleans the waterCondenser Water Pump Moves the waterCooling Tower Transfer heat from water to airFill Breaks water into small dropletsBaffles Keeps water within tower © Copyright PMFreeman
  17. 17. HVAC Stuff© cooling tower 1000 Really Tall Towerwater loop (4 - condenser water) air loop (1) air handler office water loop (2 – chilled water) Remember the roller coaster ride: the heat chiller is just a passenger in the water, which is simply carrying the refrigerant loop (3) heat where ever we want it to go . . . Copyright PMFreeman©
  18. 18. HVAC Stuff©(a common approach – but not the only approach)General goal is to take the hot outside cooling tower Once we get rid of the hot, we return cold air water refrigerant water air handler chiller office Copyright PMFreeman©
  19. 19. HVAC Stuff© Your home “split system”water loop 2 – chilled water??water loop 4 - condenser water??There are no “distance” issues, so water loops areNOT NEEDED, BUT you will notice that therefrigerant loop is extended, hence the name,“split system” since the evaporator and condenserare not adjacent refrigerant loop (3)Exterior Condenser Interior Evaporator “furnace” Copyright PMFreeman©
  20. 20. HVAC Stuff© Your home “split system” air water refrigerant water Copyright PMFreeman©
  21. 21. HVAC Stuff© cooling tower Cabinet (“Liebert”) Unit for Computer Cooling air loop (1) water loop (4 - condenser water) refrigerant loop (3) Computer Room water loop 2 – chilled water?? There are no “distance” issues, so it is NOT NEEDED Copyright PMFreeman©
  22. 22. HVAC Stuff© cooling tower SWUDs (self-contained water cooled unitary devices ) air loop (1) water loop (4 - condenser water) refrigerant loop (3) water loop 2 – chilled water?? There are no “distance” issues, so it is NOT NEEDED Copyright PMFreeman©
  23. 23. HVAC Stuff©(a Cabinet/”Liebert” unit OR SWUDself-contained water cooled unitary devices) cooling tower air water refrigerant water chiller Cabinet/”Liebert” SWUD Copyright PMFreeman©
  24. 24. HVAC Stuff©One-Story Business Park Rooftop Unit (RTU) refrigerant loop (3) water loop 2 – chilled water?? water loop 4 - condenser water?? There are no “distance” issues, so water loops are NOT NEEDED air loop (1) offices Copyright PMFreeman©
  25. 25. HVAC Stuff©(a common approach – but not the only approach)You do this one: with a one-Story cooling towerBusiness Park Rooftop Unit (RTU),which loops are unnecessary?What else is wrong with this picture? air water refrigerant water air handler chiller office Copyright PMFreeman©
  26. 26. HVAC Stuff© cooling towerWhat about Economizers? air water refrigerant water Plate heat exchanger Copyright PMFreeman©

×