More Related Content
Similar to ASHRAE_YEA_091012.pdf
Similar to ASHRAE_YEA_091012.pdf (20)
Recently uploaded
Recently uploaded (20)
ASHRAE_YEA_091012.pdf
- 3. What is VRF? • Zoning System • Two-Pipe / Three Pipe System • Packaged DDC Control • Operates as a Heat Pump • Simultaneous Cooling & Heating • Inverter Technology / Variable Speed Compressor • Multiple Indoor Units – Up to 50 Indoor Units Per System • Connected Diversity – Up to 150% • Variable Capacity Indoor Units • EMS / BMS Compatibility • High Turn Down Ratios – Below 10% In Many Cases Variable Refrigerant Flow
- 4. INVERTER Technology Changes electrical frequency from 60 Hz (line Power) to a varying range (10 Hertz to 110 Hertz – depending on the system)
- 5. INVERTER Technology Time Room Temperature Automatically adjusts compressor speed to meet load Sizing flexibility with variable capacity Strives to run long periods at lower speeds. • Reduced / eliminated cyclic losses Improved temperature control • No more minimum cycle timers – no temperature overshoot. VRF VRF V R F SETPOINT CONVENTIONAL CONVENTIONAL
- 6. AHRI Standard 1230 – VRF HAS ARRIVED ! 3.27 VRF Multi-Split System. A split system air-conditioner or heat pump incorporating a single refrigerant circuit, with one or more outdoor units, at least one variable speed compressor or an alternative compressor combination for varying the capacity of the system by three or more steps, multiple indoor fan coil units, each of which is individually metered and individually controlled by a proprietary control device and common communications network. The system shall be capable of operating either as an air conditioner or a heat pump. Variable refrigerant flow implies three or more steps of control on common, inter-connecting piping.
- 7. The Evolution VRF Example (Mitsubishi City Multi): Japan 20+ Years, Tried and Proven! Europe 15+ Years, depending on the country Latin America 10+ Years, from Mitsubishi US Bermuda 10+ Years USA since 2002!
- 8. Simultaneous Systems Components OUTDOOR UNIT Remote Controllers + BC / Branch CONTROLLER + INDOOR UNITS + or WATER-SOURCE UNIT
- 9. Typical Simultaneous 2-Pipe VRF System Layout
- 11. Typical Changeover VRF Systems Layout COOLING HEATING
- 12. Power Supply Controls Example Central Controllers Power Supply TG-2000 LAN Hub TG-2000 PC Control Remote Controllers
- 13. Building Management System (BMS) Hub Ethernet LonTalk Central Controller BACnet Building Management Systems May Be A Hardware Interface
- 15. Target Commercial Applications Buildings where zoning is required Applications where sound is important Historic Renovations Multi-Story Office Buildings Hotels Banks Universities Churches
- 16. SEACOAST PROTECTION Hospital Admin Areas / MOB – Non Procedure RESIDENTIAL BANKS Additional Applications
- 17. Building Use Occupant Load Solar Load Cooling Diversity – 3 Types
- 18. VRF Excels at Heat Recovery Applications ! Typical Winter Loads Heat CHILLER, COOLING TOWER, PUMPS Heat BOILER PUMPS $ $ Why Spend Money On Both? H e a t
- 19. BTU/$ - VRF Makes Good Sense !
- 20. Diversity - Heating Minimal Diversity Available ! Ambient Modification Charts • Available capacity decreases • Both outdoor and indoor units de-rated • Defrost Operation Evaluation of De-ratings Important! • Use tools available from VRF manufacturer to accurately access de-ratings. Auxiliary Heating Changeover Point • Try and maximize heat pump hours – depends on climate. Columbus Ohio: 90% of heating hours above 25 Deg F based on Hourly Average Weather Data. Evaluation of De-ratings Important ! • Use tools available from VRF manufacturer to accurately access de-ratings.
- 21. Typical Range Of Available VRF Systems Air Cooled 6 – 24 Ton (Simultaneous) 6 – 30 Ton (Change Over) 208/230, 460 Volt – 3 Phase 62 dB(A) Operating Sound Level Water Cooled 6 – 20 Ton (Simultaneous) 6 – 30 Ton (Change Over) 208/230, 460 Volt – 3 Phase Single Phase 3, 4 Ton (Change Over) 208/230, 1 - Phase
- 22. Partial Backup capability with multiple / twinned units. The remaining one or two units will perform backup operation Twinned Units Typically Required above 12 Tons Partial Back-up Operation
- 23. Typical Outdoor Temperature Operating Range Cooling – Can be extended with low ambient options (as low as -10 F) -20 -4 -15 5 -10 14 -5 23 0 32 5 41 10 50 15 59 20 68 25 77 30 86 35 95 40 104 45 113 50 122 o CDB o FDB Heating -24 -13 -13 -10 -20 -4 -15 5 -10 14 -5 23 0 32 5 41 10 50 15 59 20 68 25 77 30 86 35 95 40 104 o CWB o FWB Outdoor Temperature Outdoor Temperature 115 F 23 F Single Phase – Air Cooled 23 F Simultaneous Changeover – Air Cooled 115 F 23 F 115 F Extended Heat Capacity – Air Cooled Single Phase – Air Cooled 0 F 60 F Simultaneous Changeover – Air Cooled -4 F 60 F Extended Heat Capacity – Air Cooled 60 F -13 F NOT your typical Heat Pump Technology !
- 24. Extended Range Heat Pump Technology 70 o F entering air temp Not Your Typical Heat Pump ! 0 20 40 60 80 100 120 -13 -4 5 17 25 30 35 40 47 Outdoor Temperature o FWB % Heating Capacity Extended Rang VRF Standard VRF 100% 87% 75% 50%
- 25. Water-source VRF Units - Changeover Systems Heat Recovery In Water Loop Only Heat Recovery In Water Loop Only Water Circuit System System “ “A A” ” in in COOLING Mode COOLING Mode (refrigerant (refrigerant absorbing heat) absorbing heat) Heat is recovered between the units within the water loop System System “ “B B” ” in in HEATING Mode HEATING Mode (refrigerant (refrigerant discharging heat) discharging heat) PQHY Unit “A” PQHY Unit “B” Cooling Cooling Cooling Cooling Heating Heating Heating Heating
- 26. Water-source VRF Units – Simultaneous Systems Heat Recovery In Two Locations Indoor units Indoor units Water circuit Indoor units Indoor units Heat recovery Heat recovery Cooling Cooling Cooling Cooling Heating Heating Heating Heating PQRY PQRY Heat is recovered between the units within the water loop
- 27. Directly Coupled to a Lake or Pond Open Loop NO NO Directly Coupled to Ground water Open Loop Water-source VRF Units Installations not allowed! NO
- 28. Heat Exchanger Isolation Coupled to a Lake or Pond Closed Loop HX YES Heat Exchanger Isolation Coupled to Ground Water Closed Loop HX YES Water-source VRF Units Installations allowed YES
- 29. Closed Piping Loop Coupled to Earth Vertical Closed Loop YES Closed Piping Loop Coupled to Earth Horizontal Closed Loop YES Water-source VRF Units Installations allowed YES
- 31. Indoor Unit Flexibility Multiple styles ranging from 6,000 to 96,000 Btu/h Typically single phase below 6 Nominal Tons Linear Expansion Valve Variable Capacity Operation Mode: Fan, Fan, Cool, Cool, Dry, Dry, Auto Auto, Heat Heat Built in or accessory condensate removal options from factory. Typical Ventilation Air options – most models Average operating sound levels around 35 dB(A) +/-
- 32. Wall Mounted 6 - 30 MBtu/h Ceiling Suspended 15 - 36 MBtu/h Floor Standing 6 – 24 MBtu/h Product Review CITY MULTI VRF Indoor Unit Flexibility
- 33. 4 – Way Large Cassette 12 - 36 MBtu/h 4 - Way Small Cassette 8 – 15 Mbtu/h One Way Cassette 6 – 15 Mbtu/h Product Review CITY MULTI VRF Indoor Unit Flexibility
- 34. Enhanced air distribution by independent vane settings Independent Vane Control Vanes can be independently adjusted by a remote controller Fixed Horizontal Air Vanes – 4 Way Cassettes
- 35. Medium Static 6 – 54 Mbth/h High Static 15 – 96 Mbtu/h Low Profile 15 – 24 Mbtu/h Vertical Ducted 12 – 54 Mbtu/h Product Review CITY MULTI VRF Indoor Unit Flexibility – Ducted Units
- 36. Recessed Unit – St. Xavier Cathedral
- 38. Refrigerant Piping Flexibility – 2 Pipe Example 393 ft. 984 ft.- 1640 ft. 3,280 ft. 1,804 ft.-2,460 ft. 1,804 ft.-2,625 ft. Total Piping Length PIPING LENGTH` Simultaneous Air Cooled 2-Pipe Simultaneous Water Cooled 2-Pipe Changeover Air Cooled 2-Pipe Changeover Water Cooled 2-Pipe Single Phase Air Cooled Farthest Indoor unit 541 ft. 541 ft. 541 ft. 541 ft. 262 ft. PIPING HEIGHT Simultaneous Air Water Cooled 2-Pipe Changeover Air Water Cooled 2-Pipe Single Phase Air cooled Outdoor Unit HIGHER than Indoor Unit 164 ft.* 98 ft. Outdoor Unit LOWER than Indoor Unit 131 ft. 65 ft. Indoor Unit to Any BC Controller 49 ft. n/a n/a
- 39. Two Pipe Example • Soft Copper BC to IU • Reducers possible at BC • Soft Copper BC to IU • Reducers possible at BC 12 indoor-unit system – Heat Recovery 12 indoor-unit system – Heat Recovery
- 40. Three Pipe Example • Hard copper from OU to BS • Reducer fittings • Hard copper from OU to BS • Reducer fittings 12 indoor-unit system – Heat Recovery 12 indoor-unit system – Heat Recovery
- 41. Refrigerant Leakage Concentration Levels What is RCL? Refrigerant Concentration Limit (RCL): “the refrigerant concentration limit, in air, determined in accordance with this standard and intended to reduce the risks of acute toxicity asphyxiation and flammability hazards in normally occupied, enclosed spaces” RCL typically expressed as lbs/1000 ft3
- 42. Determination of RCL Referenced Codes/Standards International Mechanical Code • Previously set RCL for R-410A at 10 lbs/MCF • 2009 Revisions raises RCL to 25 lbs/MCF ISO-5149 • ISO-5149 sets R-410A RCL as 18.7 lbs/MCF ASHRAE 15-2007 • ASHRAE 15-2007 establishes the R-410A RCL as 25lbs/MCF through reference to ASHRAE 34.
- 43. Critical Concentration Calculation RCL (R410A) = 25 lb./Mcf Refrigerant Charge (Rc) of a P72 = 23 lbs 3 oz = 23.1875 lbs MAV = Minimum Applied Volume (cubic feet) MAV = Rc/RCL MAV = (23.1875 lbs)/(25 lbs/1000 cu ft) MAV = 927.5 cu ft
- 44. Appropriate Solutions Option 1-Locate Equipment within larger space •Ducted communicating spaces w/ no closure devices that restrict airflow below 10% of peak airflow. Option 2-Do not use equipment with refrigerant Option 3-Increase room volume through the use of openings •Door Undercuts, transfer ducts or grilles. Option 1 Option 2 Option 3
- 45. • Inverter-driven compressors / part load performance ! • Variable capacity indoor units ! • Extended Heat Pump (Air to Air) Capability ! • Simultaneous cooling and heating ! The Efficiencies from “VRF System Effect”
- 46. Summary of Refrigerant Management Refrigerant Concentration Limit is a tool to protect the public Informed and educated engineers can incorporate necessary measures to meet the RCL. R410A is of lowest toxicity and is NOT combustible.
- 47. Energy Standards Energy Standards Savings Savings
- 48. AHRI 1230 IEER AHRI Standard 1230 created a testing standard for VRF equipment above 65,000 Btu/h (below 65,000 Btu/h continues to be rated in accordance with AHRI Standard 210/240-2008) On January 1st, 2010, IEER superseded IPLV as the testing standard for VRF equipment above 65,000 Btu/h Unlike testing VRF for IPLV (according to AHRI Standard 210/240), testing for IEER involves actual testing at part load conditions and assigning weighted values to each test point Testing VRF for IEER involves testing at four fixed conditions: 100%, 75%, 50%, 25% load. The equipment is still not allowed to vary compressor speed and indoor unit capacity to meet a varying load as it was designed to do Simultaneous Heating and Cooling Efficiency (Not Yet Tested) SCHE = (Heating Capacity (Btu/h) + Cooling Capacity (Btu/h)) / Total System Power Input (Watts)
- 49. ASHRAE 90.1-2010 VRF Benchmarks
- 50. ASHRAE 90.1-2010 VRF Benchmarks
- 52. Energy Modeling EnergyPro Version 5.0 Accepted by the USGBC for Compliance with Energy and Atmosphere Credit 1
- 53. Sample Building in Part Load: OA Temp 50oF Simultaneous Load: Cooling: 27000 BTU Heating: 21000 BTU 3000 BTU 6000 BTU 3000 BTU 3000 BTU 3000 BTU Elect Janitor Break Room Lobby/ Waiting Room Conference Room Office #1 Office #2 Cubicle Area Open Work Room 6000 BTU 12000 BTU 6000 BTU 3000 BTU 3000 BTU Women Men PURY-P72 What Makes Energy Pro Different
- 54. What Makes Energy Pro Different Cooling Power Input PURY-P72 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 0 12000 24000 36000 48000 60000 72000 84000 System Load BTUH Power Input KW 72,000 BTUH 6.48 KW 27,000 BTUH 2.38 KW
- 55. What Makes Energy Pro Different Outdoor Temperature Power Input Correction (For a 68 Indoor WB Temperature) 1.5000 1.6000 1.7000 1.8000 1.9000 2.0000 2.1000 2.2000 2.3000 2.4000 0 10 20 30 40 50 60 70 80 90 100 OA Temperature FDB Powe r Input K W 2.38 KW at 95oF 1.87 KW at 50oF
- 56. What does this mean Getting 27,000 BTUH of cooling and 21,000 BTUH of heating, while providing only 1.87 KW to the outdoor unit. This savings cannot be realized without the ability to model simultaneous heating and cooling. For this scenario, Calculated Efficiency of 25.7 EER
- 57. School Energy Modeling Results School--Percentage Energy Cost Savings V/S Comparable Systems 0% 4% 7% 11% 14% 18% 21% 25% 28% 32% Atlanta Miami Boston NYC Chicago Dallas LA Seattle Location Energy Savings CM v/s VAV CM v/s 4 Pipe CM v/s WSHP
- 58. Office Building Energy Modeling Results Percentage Energy Savings V/S Comparable Systems 0% 4% 7% 11% 14% 18% 21% 25% Atlanta Miami Boston NYC Chicago Dallas LA Seattle Location Energy Savings CM v/s 4 Pipe CM v/s VAV CM v/s WSHP
- 59. Questions Answers Thank You For Having Us Today! We Are Here To Help Make Your VRF Projects Successful !