2015 HVAC Excellence Educator Conference Variable Refrigerant Flow & Variable Refrigerant Temperature Slide 1
Residential Market Push for more efficiency Green Building Initiative R-22 & High Efficiency Footprint & Technology Variable Air Volume/Zoning Commercial VAV Residential Zoning Efficiency & End-user comfort generally applied to the airside Slide 2
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Load Load Compressor Multi-Step Control Standard HVAC System 1 to 2 stages of capacity Mechanical Unloading VRV/VRF Technology Inverter Controlled Multiple Capacity Steps Electronic inverter varies compressor rotational speed in steps Unloader Principle Multi-Step Control Principle 50% 100% 52~230Hz Compressor capacity Applied frequency Slide 5
Residential Equipment Slide 6
One to One Mini Split & Multi Splits Slide 7
DX Refrigeration Cycle Cooling Mode Slide 8
DX Refrigeration Cycle Heating Mode Slide 9
VRF Commercial Slide 10
What is VRF? Variable Refrigerant Flow Also referred to as VRV Variable Refrigerant Volume VRV is a registered trademark Slide 11
Variable Refrigerant Flow Outdoor Unit Indoor Units Main features Energy Saving Inverter technology Individual control Ideal for zoning Long refrigerant piping runs Wide range of indoor units Low Noise Levels Slide 12
Advanced Zoning Capabilities Total comfort for occupants Office buildings Hospitals Assisted living facilities Schools Hotels Retail space Reduced operating costs Shut down zones that are not in use Variable capacity design enables maximization of diversity Each zone is individually controlled Slide 13
Heat Pump - Cooling Slide 14
Heat Pump - Heating Slide 15
Detail Low Temp. Ref. exchange Enthalpy High Temp. Ref. Slide 16
VRF Beginning Slide 17
Background 1973 Global oil crises 1979 New energy efficiency laws passes in Japan 1980 Chiller design engineers challenged with making a higher efficiency chiller 1982 The worlds first VRF System is launched Slide 18
Why Refrigerant? Heat Transfer Media The commonly used methods of Heat Transfer in Air Conditioning Solutions each exercise different operational characteristics regarding adding or removing heat energy in a conditioned space as follows: - Air Water Refrigerant 0.14 watts/lb 2.6 watts/lb 25 watts/lb VAV VWV VRF This diagram represents the Energy Transfer possible per lb of media due to the performance characteristic of the fluid used. Slide 19
Clearance & Crawlspace 6-Ton Ductwork 30-Ton Refrigerant Pipework VRF meets VAV Slide 20
VRF Concept Multiple indoor units connected to one outdoor unit Up to 64 on a single refrigerant piping network Available in either air cooled or water cooled Slide 21
VRF Concept Think of a VRF system as a chiller that circulates refrigerant to each zone instead of water A heat pump system is equivalent to a 2 pipe chiller Major benefit is smaller heat/cool changeover zones due to the modular build up A heat recovery system is equivalent to a 4 pipe chiller system Heat Pump Heat recovery 6 Ton 6 Ton 12 Ton Cooling Cooling Heating Heating Slide 22
VRF Refrigerant Distribution Standard refrigerant balancing joint and header JOINT HEADER Slide 23
Flexible Communication A simple 2 wire daisy chain communication system 16-18 gauge AWG Not polarity sensitive Up to 6560ft of total system wiring Longest length up to 3280ft Auto Addressing Cost savings at installation Cost savings at commissioning Slide 24
VRF Capacity Control and Zoning T2 EACH INDOOR CONTROLS ITS CAPACITY VIA PID CONTROL AND AN E.E.V. T3 CPU (PID Control) T4 Controller (T SET ) 1 2 3 4 OUTDOOR UNIT ADJUSTS THE INVERTER COMPRESSOR TO PROVIDE THE REQUIRED CAPACITY (Large or Small) T1 INDEPENDENT BRAIN LEGEND T1: Refrigerant Liquid Line Temp. T2: Refrigerant Suction Line Temp. T3: Return Air / Remote Sensor Temp. T4: Controller Temperature Sensor T SET : Controller Set Point Temp. Slide 25
VRF Equipment Slide 26
Air Cooled 3-Phase Equipment Heat Pump Heat Recovery Single Fan Dual Fan Single Module Double Module Triple Module 6 to 30 Ton Capacity 208/230 & 460 3 Phase Slide 27
Water Cooled 3-Phase Systems Geothermal Application With Limits 6 to 21Ton Capacity 208/230 3 Phase Slide 28
Air Cooled Single Phase 208/230 Single Phase Slide 29
VRV/VRF Indoor Units + Slide 30
VRF Control Capability Individual Zone Controllers Multi-zone (Centralized) Controllers Open Protocol Gateways Adapter PCB s Slide 31
Technology Slide 32
Inverter Technology +V T(sec) -V Frequency (Hz) +V T(sec) -V Frequency (Hz) Slide 33
Inverter Boards have several capacitors. Technicians must allow time for capacitors to discharge before servicing system. Inverter controlled systems use both AC and DC voltage during operation. Check VOM settings when diagnosing system. Magnetic parts trays should not be placed on or near any printed circuit boards on Inverter driven equipment. Slide 34
Performance & Efficiency Slide 35
Part Load Efficiencies Average Load 75% of total operation hours less than 70% of full load VRV III 8-ton system 6 amps VRV III 8-ton system 30 amps Slide 36
Efficiency Slide 37
Flexibility Slide 38
VRV/VRF Refrigerant Piping Flexibility Condenser to farthest fan coil VRVIII-S: 490 ft VRVIII: 540 ft VRV WIII: 390 ft 1 st RefNet to farthest fan coil VRVIII-S: 130 ft VRVIII: 130 ft (295 ft) VRV WIII: 130 ft RefNet to fan coil: 130 ft (all) Vertical Separation Condenser to highest fan coil VRVIII-S: 130 ft VRVIII: 295 ft VRV WIII: 131 ft Condenser to lowest fan coil VRVIII-S: 164 ft VRVIII: 164 ft (295 ft) VRV WIII: 164 ft Max. combined piping VRVIII-S/VRV WIII: 1,000 ft VRVIII: 3,280 ft 49 ft Slide 39
Eldorado Business Tower In a High-rise office building Slide 40
VRV/VRF Refrigerant Piping Flexibility Building Profile Location : Sao Paul BZ. Office building Height : 33F + B3 Total Floor area : 728,178 ft2 Typical floor area: 17,222 ft2 Completion : 2007 Slide 41
VRV/VRF ODU Location 217 ft 384 ft 167 ft Slide 42
VRV/VRF ODU on Roof 217 ft 1454 Tons 167 ft Slide 43
VRV/VRF ODU on Lower Level 217 ft 167 ft 1259 Tons Slide 44
Installation Floor by Floor Condensers have the flexibility to be installed in equipment rooms. The O.D. Fan performance can be increased to accommodate ducted discharge air. A simple field setting will increase the fan static pressure. Discharge Air 0.12 W.G Standard 0.32 W.G HIGH Slide 45
VRV/VRF Design Flexibility Wide range of indoor capacity to fit to your room Ducted and Ductless 0.6 Ton Room 2 Room 1 8 Ton Slide 46
Part Load Operation Ideal for Random Occupancy Slide 47
VRV/VRF Reduced Installation Costs They fit in the elevator SMALL FOOTPRINT Slide 48
Heat Recovery Slide 49
VRV III REYQ VRV WIII OR FXMQ_M Ducted unit Branch Selector Box FXMQ_P DC Ducted Unit BSVQ _VRVIII BRCIE71 Programmable Advanced Zone Control Slide 50
Branch Selector Box Provides Heating/Cooling changeover to the connected fan coil or fan coils EEV refrigerant control Brazed refrigerant connections Line Voltage powered Single Port Model Numbers: BSVQ36PVJU 36,000 Btu - Up to 5 FC s BSVQ60PVJU 60,000 Btu - Up to 8 FC s BSVQ96PVJU 96,000 Btu - Up to 8 FC s ELECTRONIC EXPANSION VALVES 208-230vac. Liquid pipe ELECTRONIC EXPANSION VALVE High/low pressure gas pipe Suction gas pipe Slide 51
EV CD EV CD Cool to Heat EV CD EV CD FAN OFF Heat STANDBY No system interruption 6 min. EV CD EV CD HOT START Slide 52
Individual zone control for heat and cool operation Dual Press Gas Pipe Liquid Pipe Suction Pipe Daikin Branch Selector Boxes Cool Only BS Box BS Box BS Box BS Box BS Box Slide 53
Heat Recovery - Cooling Slide 54
Heat Recovery Partial Heating Slide 55
Pressure R1T R5T R4T R21T R2T R6T R1T R3T Temperature Enthalpy Slide 56
Pressure Pressure SCT LIQUID Now SCT LIQUID The Future 105 92 Heat Rejection 3 2 92 3 Heat Rejection 2 Reduced Lift 52 Reduced Lift SST 42 A Refrigerant Effect (Capacity) Enthalpy 1 VAPOR SST 42 A Refrigerant Effect (Capacity) Enthalpy 1 VAPOR Lower Lift = Less Work = Lower power input Think Chilled Water or Boiler temperature reset function Slide 57
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Variable Refrigerant Temperature control puts you in control of how the VRV IV operates, allowing customized, exact design based on the design and climate situation Automatic* Floating weatherdependent T E Powerful Quick Mild* Providing the best balance between comfort and efficiency. The system will automatically adapt to the building and climate conditions. * Default factory settings Variable Refrigerant Temperature control High-sensible Powerful Quick Mild Eco Mode for the use of a certain refrigerant temperature. The system will only deviate from the desired refrigerant temperature if allowed and if the load requires it (only load dependent) Basic No submodes Slide 59
System capacity Automatic VRT mode Higher refrigerant temperature (Rt) in mid-season As outdoor temperature falls, the capacity of the system is adjusted by reducing the speed of compressors AND by increasing the evaporation temperature Refrigerant T Capacity & Load Fixed Rt 68 68 Variable Rt 77 86 77 86 Example: cooling 95 Cooling requirement 95 Design point Efficiency increases thanks to lower compression ratio and maintaining optimal compressor speed Efficiency 68 77 86 95 Outdoor temperature Slide 60
Compressor efficiency Efficiency Benefit With a higher refrigerant temperature, the compression ratio falls so the compressor doesn t have to work so hard. This prevents it from operating at a less efficient low operating speed. Nominal efficiency Efficiency curve: T E = 52 F / T C = 95 F Efficiency curve: T E = 48 F / T C = 95 F Efficiency curve: T E = 43 F / T C = 95 F 20 40 60 80 100 120 140 160 Compressor frequency [rps] Slide 61
Compressor efficiency Efficiency Benefit With a higher refrigerant temperature, the compression ratio falls so the compressor doesn t have to work so hard. This prevents it from operating at it a less efficient low operating speeds. OPTIMAL COMPRESSOR EFFICIENCY ZONE (EFFICIENCY ISLAND) Nominal efficiency Efficiency curve: T E = 52 F / T C = 95 F Efficiency curve: T E = 48 F / T C = 95 F Efficiency curve: T E = 43 F / T C = 95 F 20 40 60 80 100 120 140 160 Compressor frequency [rps] Slide 62
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Skills & Tools for the Future Slide 64
Heat Pump Gauge Flaring Tool Flare Gauge Model #: MT2HP Model #: BFT850FN Model #: DACA-FSG-1 Torque Wrench Deburring Tool Tubing Cutter Model #: TLTWSAE/TLTWSM Model #: BTLDB3 Model #: BTC300 Slide 65
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Core Remover Tool Hex Set (SAE) Hex Set (Metric) Model #: TLVC410A Adapter Fittings 1/4 to 5/16 Angle/Swivel Model #: AD87S 5/64" thru 1/4" Model #: TLSWH Adapter Fittings 1/4 to 5/16 Adapter Model #: AD87 1.5mm thru 8mm Model #: TLSWHM Service Port Caps 5/16 Caps Model #: AD87 Slide 67
Nitrogen Regulator (700 PSI min) Vacuum Pump Nitrogen regulator capable of measuring up to 700 plus PSI is necessary for pressurizing systems to 550 PSIG Having a properly maintained vacuum pump is important for evacuating a refrigerant system Pump capacity minimum of 2 cfm Digital Micron Gauge Digital Scale Vacuum Gauge w/digital Display Using a micron gauge for the entire evacuation process is mandatory on all Daikin systems A good digital scale must be used to properly weigh in the liquid R-410A refrigerant Slide 68
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Thank You Slide 73