Introduction to Variable Refrigerant Flow Systems

1. Introduction to Variable Refrigerant Flow Systems Allen Anaya Application Consultant WM Carroll, LLC Ph: 505-268-6776 Cell: 505-385-7338 Fax: 505-255-1329 E-Mail: Allen@wmcarroll.com NM ASHRAE – Introduction to Variable Refrigerant Systems

2. Agenda • What is VRF? • History • Concept • How does VRF Operate? • Refrigerant • Compressor • Fan Coil • Important Standards • ASHRAE Standard 15 • AHRI-1230-2010 • VRF Benefits • Installation & Design Flexibility • User Comfort • The Future of VRF in North America NM ASHRAE – Introduction to Variable Refrigerant Systems

3. Variable Refrigerant Flow What is VRF? V R F Also referred to as VRV ® – Variable Refrigerant Volume VRV is a registered trademark NM ASHRAE – Introduction to Variable Refrigerant Systems

4. 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 VRF History NM ASHRAE – Introduction to Variable Refrigerant Systems

5. VRF world first’s VRF Global History World’s first CO 2 VRF system is developed VRF is launched globally First globally available heat recovery VRF Worlds first R410A VRF Industry changing piping and defrost technology 1982 2003 2005 1991 1987 1998 2008 1990 2007 World’s first VRF system is developed Worlds inverter driven VRF First water cooled VRF system is launch in the USA World’s first R407C VRF system is developed NM ASHRAE – Introduction to Variable Refrigerant Systems

6. Development of VRF Market Japan Buildings under 70,000ft2 • By 1996 VRF had established itself as a proven technology with 34% market share • With increased market acceptance as a replacement to traditional applied central systems VRF achieved 47% market share by 2001 • 9% share was taken from the chiller/central plant market • The 4% taken from the split and package section was through replacing VAV projects and allowing customer to afford the “chiller” they originally wanted 2001 1996

7. Development of VRF Market Japan Buildings over 70,000ft2 • Further evidence of acceptance can be seen by the increase in VRF market share in the larger applications • 12% share taken from the chiller/central plant market • This trend was common in Europe, Australia and now North America 1996 2001

8. Simple system Complicated Energy efficient Outdoor unit Cooling tower Space-conscious design Pump Water piping Refrigerant piping FCU FCU Pump AHU Inefficient part load operation indoor unit Remote controller For cooling For heating Individual control Managed by engineer 2 heat sources Simple Operation VRF Concept VRF Chiller NM ASHRAE – Introduction to Variable Refrigerant Systems

9. VRF Concept Simple system Space-conscious design Individual control Simple Installation Simple Operation Simple Maintenance One Manufacturer Top floor Building floors One Point Of Contact For Technical Support Remote controllers NM ASHRAE – Introduction to Variable Refrigerant Systems

10. 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 12 Ton Cooling Cooling Cooling Cooling Heating Heating Heating Heating 6 Ton NM ASHRAE – Introduction to Variable Refrigerant Systems

11. VRF Concept HEAT RECOVERY VRF NM ASHRAE – Introduction to Variable Refrigerant Systems

12. VRF Concept 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 NM ASHRAE – Introduction to Variable Refrigerant Systems

13. VRF Concept Where does a VRF system position? • VRF has the following attributes:- • Energy Efficient • Tight Temperature Control • Quiet Operation • The Ability To Have Many Zones • Large Capacity (Modular Build Up) • Centralized Plant (long piping) • Advanced BAS Control • Premium Specification & Priced Product • Special Advantage of Modular Design: If you loose 1 condenser, you only loose a small part of the building; NOT the entire building. • Modular design only requires installation of a zone as required; entire cooling and heating system does not have to be piped during initial construction VRF competes most naturally as a chiller. (this doesn’t mean it can only compete with chillers) NM ASHRAE – Introduction to Variable Refrigerant Systems

14. Agenda • What is VRF? • History • Concept • How does VRF Operate? • Refrigerant • Compressor • Fan Coil • Important Standards • ASHRAE Standard 15 • AHRI-1230-2010 • VRF Benefits • Installation & Design Flexibility • User Comfort • The Future of VRF in North America NM ASHRAE – Introduction to Variable Refrigerant Systems

15. HEAT TRANSFER MEDIA Air Water 0.46 Btuh/lb Refrigerant 8.98 Btuh/lb 88.2 Btuh/lb VAV VWV VRF How does VRF Operate? NM ASHRAE – Introduction to Variable Refrigerant Systems

16. +V T(sec) -V Frequency (Hz) Inverter Box +V T(sec) -V Frequency (Hz) How does VRF Operate? Inverter Drive System • The inverter control adjusts the supply frequency • Thus the rotational speed of the compressor is controlled • Exactly the right amount of refrigerant gas is pumped to meet the cooling requirements NM ASHRAE – Introduction to Variable Refrigerant Systems

17. How does VRF Operate? Inverter = Energy Efficiency • The start/stop cycle is repeated less frequently – reducing energy loss at startup • As room temperature nears set point capacity is automatically “throttled down” • Capacity is regulated when outdoor temperature changes • Startup time is reduced by 1/3 NM ASHRAE – Introduction to Variable Refrigerant Systems

18. How does VRF Operate? Other Inverter Benefits • Very low startup amperage • No locked rotor amps • No stress on windings or compressor frame • No “light flicker” • Lubrication of bearings increases before speed increases • System pressures increase gradually reducing noise and stress on piping • Quiet compressor startup NM ASHRAE – Introduction to Variable Refrigerant Systems

19. How does VRF Operate? Other Inverter Benefits • Longer Run Periods at Lower Capacities • Better Dehumidification • Fewer compressor starts mean less wear and tear on the compressor = longer life! • Lower compressor speeds = higher system efficiency since the condenser coil surface remains large in relation to reduced capacity • Higher efficiency = Lower electric bills! NM ASHRAE – Introduction to Variable Refrigerant Systems

20. PID Control Signal Valve Mechanism Inlet Outlet How does VRF Operate? Electronic Expansion Valve (EEV) Control • EEV’s receive ‘PID’ control feedback to adjust refrigerant volume • Up to 2000 steps of control • Continual management of flow rate controls super heat and coil capacity for optimum performance and energy efficiency NM ASHRAE – Introduction to Variable Refrigerant Systems

21. How does VRF Operate? Proportional, Integral & Derivative (PID) • Electronic expansion valve using PID • Continuously adjusts the refrigerant volume in response to load variations • Comfortable room temperature is maintained without the wide temperature swings of a conventional system T2 LEGEND T1: Refrigerant Liquid Line Temp. T2: Refrigerant Suction Line Temp. T3: Return Air / Remote Sensor Temp. T4: Controller Temperature Sensor TSET: Controller Set Point Temp. CPU (PID Control) T4 Controller (TSET) T1 NM ASHRAE – Introduction to Variable Refrigerant Systems

22. System Capacity Control T2 CPU (PID Control) T3 T4 Controller (TSET) T1 How does VRF Operate? EACH INDOOR CONTROLS ITS CAPACITY VIA PID CONTROL AND AN E.E.V. 2 3 1 4 LEGEND T1: Refrigerant Liquid Line Temp. T2: Refrigerant Suction Line Temp. T3: Return Air / Remote Sensor Temp. T4: Controller Temperature Sensor TSET: Controller Set Point Temp. CONDENSING UNIT ADJUST THE INVERTER COMPRESSOR TO PROVIDE THE REQUIRED CAPACITY (Large or Small) NM ASHRAE – Introduction to Variable Refrigerant Systems

23. 100 DC Motor 90 AC Fan Motor DC Fan Motor Approx. 20% increase Approx. 40% increase Motor Efficiency [%] Magnet 80 AC Motor 70 10 20 30 40 50 60 70 80 90 100 110 Revolutions [rps] How does VRF Operate? DC Fan Motor Efficiency • Efficiency improved in all areas compared to conventional AC motors, especially at low speeds NM ASHRAE – Introduction to Variable Refrigerant Systems

24. Agenda • What is VRF? • History • Concept • How does VRF Operate? • Refrigerant • Compressor • Fan Coil • Important Standards • ASHRAE Standard 15 • AHRI-1230-2010 • VRF Benefits • Installation & Design Flexibility • User Comfort • The Future of VRF in North America NM ASHRAE – Introduction to Variable Refrigerant Systems

25. Overview of ASHRAE Std 15 Important Standards / Code Information • Specifies minimum safety requirements in the event of a refrigerant leak into an occupied space. • Safety Issues: • Flammable refrigerants causing injury or death by fire. • Toxic refrigerants possibly causing injury or death by poisoning. • Non flammable and non toxic refrigerants causing injury or death by asphyxiation from oxygen displacement. NM ASHRAE – Introduction to Variable Refrigerant Systems

26. Scope of Standard 15 Important Standards / Code Information • Scope • 2.1 This standard establishes safeguards for life, limb, health, and property and prescribes safety requirements. • 2.2 This standard applies • To the design, construction, test, installation, operation, and inspection of mechanical and absorption refrigeration systems, including heat pump systems used in stationary applications, • To modifications including replacement of parts or components if they are not identical in function and capacity, and • To substitutions of refrigerant having a different designation. NM ASHRAE – Introduction to Variable Refrigerant Systems

27. Basic Steps Important Standards / Code Information • Determine volume of smallest occupied space (cu.ft.) • Determine refrigerant qty potential of the smallest occupied space (lbs) • Check that refrigerant qty potential doesn’t exceed the allowable Refrigerant Concentration Limit (RCL) per 1000cuft. • Check routing of piping (must be non obstructive) in corridors, lobbies and versus the RCL requirements NM ASHRAE – Introduction to Variable Refrigerant Systems

28. Compliance Responsibilities Important Standards / Code Information • Specifies application, not manufacturing requirements. • Impossible for a unit to comply, only an application can comply. • Design engineer is responsible for assessment and compliance. • ASHRAE Std 15 has an easy to follow “Users Handbook” that can be purchased by the Engineer / Contractor. • All units should comply with mandatory U.S. manufacturing standards. • ASHRAE Std 15 equivalent standards exist in Europe and Asia and are just as stringent. “Direct” systems such as VRF are the most common solution in these regions and are applied successfully to meet these standards NM ASHRAE – Introduction to Variable Refrigerant Systems

29. Current Situation All VRF Equipment is currently sold under a waiver from the DOE No available testing and rating standard This means that only full load EER and COP can be published Advantage can not be taken of the true VRV system benefits:- Part load performance Low ambient heating capabilities Important Standards / Code Information NM ASHRAE – Introduction to Variable Refrigerant Systems

30. Important Standards / Code Information AHRI 1230 • The industry has been working on the VRF testing and rating standard for the last 5 years • Now, the hard work has paid off! • We are proud to announce that the VRF testing and rating standard, AHRI 1230, will be launched and the efficiency levels will be in ASHRAE 90.1 by January 2011

31. AHRI-1230 Explanation of the Ratings All efficiency values will be based on the total system performance including:- Outdoor unit power input Power input of indoor units Piping loss correction factors to reflect real life building performance With this; We can now promote efficiency levels for Ducted, Ductless and Mixed combinations Important Standards / Code Information NM ASHRAE – Introduction to Variable Refrigerant Systems

32. Agenda • What is VRF? • History • Concept • How does VRF Operate? • Refrigerant • Compressor • Fan Coil • Important Standards • ASHRAE Standard 15 • AHRI-1230-2010 • VRF Benefits • Installation & Design Flexibility • User Comfort • The Future of VRF in North America NM ASHRAE – Introduction to Variable Refrigerant Systems

33. VRF/VRV Benefits Outdoor Unit Indoor Units • Main features • Energy Saving • Individual control • Long refrigerant Piping • Wide range of units • Low Noise Level NM ASHRAE – Introduction to Variable Refrigerant Systems

34. Users Comfort Accurate Temperature Control VRF system Conventional A/C 30 Room Temperature 25 20 Down to 1F Cooling mode with VRF System: 15 Min.. 10 20 30 40 50 60 70 VRF/VRV Benefits NM ASHRAE – Introduction to Variable Refrigerant Systems

35. Ductless operating sound levels as low as 28dB(A) Ducted operating sound Levels as low as 35dB(A) User Comfort Low Operating Sound VRF/VRV Benefits NM ASHRAE – Introduction to Variable Refrigerant Systems

36. VRV System Conventional System VRF/VRV Benefits Lightweight, Small & Flexible • Indoor units are lightweight and compact • Fit into nearly any ceiling space • Outdoor units don’t require special cranes or lifting devices • Can be hauled using a hand-lift and the building elevator • Installation by floor • If necessary, installation can be done by floor • No need to wait until the full system is installed to test the system sections NM ASHRAE – Introduction to Variable Refrigerant Systems

37. VRF/VRV Benefits Reduced Intallation Space For 10 Tons capacity Refrigerant R-410A Water Ø 1/2“ Ø 2“ Ø 2“ Ø 1-1/8“ Air 24“ 49“ Ø 25 ½“ Always two ducts needed 24“ 16“ or or NM ASHRAE – Introduction to Variable Refrigerant Systems

38. Advanced Controls Solutions VRF/VRV Benefits ~ Ethernet (for use in Lon Works networks) BMS Fire alarm Security ~ HRV Power supply facility NM ASHRAE – Introduction to Variable Refrigerant Systems

39. Agenda • What is VRF? • History • Concept • How does VRF Operate? • Refrigerant • Compressor • Fan Coil • Important Standards • ASHRAE Standard 15 • AHRI-1230-2010 • VRF Benefits • Installation & Design Flexibility • User Comfort • The Future of VRF in North America NM ASHRAE – Introduction to Variable Refrigerant Systems

40. Worlds First CO2 VRF This year; the worlds first CO2 based VRF System was released for sale in Europe One of the most environmentally friendly refrigerants with a GWP of 1 New Technologies New optimized swing compressor to handle the higher pressures and reduce leakage Dual stage intercooler to help control the refrigerant and reduce pipe dimensions New 3 row heat exchanger and pass pattern for optimum heat transfer The Future of VRF in North America NM ASHRAE – Introduction to Variable Refrigerant Systems

41. The Future of VRF in North America What’s Next: Domestic and Hot Water Heating NM ASHRAE – Introduction to Variable Refrigerant Systems

42. Conclusion VRF provides and alternative, realistic choice to traditional central systems. It captures many of the features of chilled water systems, while incorporating the simplicity of DX systems. Allows for the correct equipment selection with both air cooled and water cooled equipment It brings some of the latest technology to the market and provides a higher degree of reliability, comfort and energy efficiency that is expected from today's consumer. NM ASHRAE – Introduction to Variable Refrigerant Systems

43. Introduction to Variable Refrigerant Flow Systems Thank You! Allen Anaya Application Consultant WM Carroll, LLC Ph: 505-268-6776 Cell: 505-385-7338 Fax: 505-255-1329 E-Mail: Allen@wmcarroll.com NM ASHRAE – Introduction to Variable Refrigerant Systems