solving problems using variable refrigerant flo€¦ · · 2011-08-26chiller as high as 57 db(a)...
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Solving Problems using Variable Refrigerant Flow
Today’s Agenda
• New Construction Challenges
• Renovation Challenges
• Other Discussion points
Your friendly tour guide John Brantley, PELEED AP®, CEM®
Mitsubishi Electric HVAC Commercial Area Manager
•Engineering Support
•Contractor Support
•Owner Support
•Primary lines: Mitsubishi, Carrier, Bard, Data Aire, FHP, Munters
•Works with utilities, financing, ESCO’s, ETS, others
•Largest HVAC Distributor in the Southeast
•Over 30 locations in 5 states
•Premier Commercial Distributor in southern United States
What is VRF Technology?
Variable
Refrigerant
Flow
Primary System AttributesZoning Energy Efficiency
Simultaneous Heating and CoolingMultiple Indoor Units
Integral Control System
Variable Capacity Indoor Units
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VRF Heat Recovery Technology
Simultaneous cooling and heating
2 pipes
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VRF Heat Pump Technology
COOLING
HEATING
New Facility Construction Challenges
• Reducing Energy Consumption• Providing Desired Comfort Levels• Reducing Maintenance Costs• Sound Level Constraints• Installed Costs
New Facility Construction Challenges
• Reducing Energy Consumption• Providing Desired Comfort Levels• Reducing Maintenance Costs• Sound Level Constraints• Installed Costs
How much electricity has How much electricity has Mitsubishi Mitsubishi Electric savedElectric saved in U.S. homes over the in U.S. homes over the
last last 10 years?10 years?
21,000 HomesOff the Grid
189,000 MWH(189 Million KWH)
Saved $18.9 Millionfor Homeowners
Superb System Efficiencies• Variable Refrigerant Flow can provide energy savings
around 25 to 30% over other system types
• Using heat pump technology with COP’s greater than 2.0 at 17 deg yields tremendous heating savings
• Variable Refrigerant Flow is a proven energy saving technology as evidenced by thousands of installations
New Facility Construction Challenges
• Reducing Energy Consumption• Providing Desired Comfort Levels• Reducing Maintenance Costs• Sound Level Constraints• Installed Costs
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Optimal Comfort System
Simultaneous cooling and heating
2 pipes
Indoor Comfort Flexibility
Floor standing unitWall-mounted unit Ceiling-suspended unit
Indoor Comfort Flexibility
Vertical ducted unitMedium static ducted unit
High static ducted unit Low-profile ducted unit
Product Review
4-way large cassette
Indoor Comfort Flexibility
4-way small cassette
1-way cassette
New Facility Construction Challenges
• Reducing Energy Consumption• Providing Desired Comfort Levels• Reducing Maintenance Costs• Sound Level Constraints• Installed Costs
Recommended Maintenance Schedule
Clean indoor unit air filtersRecommended every 30 days
Clean indoor and outdoor unit coilsRecommended annually
No Longer Required Maintenance
• Water Quality• Testing and Balancing• Belt Changes
• PTAC Replacement!!
New Facility Construction Challenges
• Reducing Energy Consumption• Providing Desired Comfort Levels• Reducing Maintenance Costs• Sound Level Constraints• Installed Costs
How LOUD is a traditional HVAC unit?
What Does QUIET Sound Like?What Does QUIET Sound Like?
33 dB(A)Library
50 dB(A)Refrigerator
60 dB(A)Conversation
78 dB(A)Vacuum
25 dB(A)Recording
Studio
65-75 dB(A)
Residential3-ton
HVAC Unit
How QUIET are VRF Systems?
50-60 dB(A)
PTACUnit
90 dB(A)Motorcycle
As low as19 dB(A)
Indoor Unit
As low as23 dB(A)
Ducted Unit CommercialOutdoor Unit
As low as61 dB(A)
100 dB(A)Hand Drill
70 dB(A)Busy Traffic
40 dB(A)Quiet Home
75-85 dB(A)
Air-cooledChiller
As high as57 dB(A)
Single PhaseOutdoor Unit
As low as46 dB(A)
New Facility Construction Challenges
• Reducing Energy Consumption• Providing Desired Comfort Levels• Reducing Maintenance Costs• Sound Level Constraints• Installed Costs
VRF Installed Cost• Proper analysis of VRF Installed Cost must
evaluate changes in all areas of construction (electrical, architectural, etc…)
• Air Cooled VRF should be comparable in first cost with WSHP
• Air Cooled VRF should be cheaper installed than four pipe systems
Renovation Project Challenges
• Limited/Insufficient Electric Service• Adequate space to install systems
Renovation Project Challenges
• Limited/Insufficient Electric Service• Adequate space to install systems
Electrical Comparison• 100 ton cooling load system using 50 (2) ton
zones• In heating fan coils are providing approx 100
deg supply air temp with 70 deg RA using 2 KW/ton resistance heat and 50% airflow
• All systems are provided neutral outside air year round by a separate system
2 Pipe VRF Design• (5) 20 ton systems with (10) 2 ton ducted air
handlers per systemSystem MCA/Unit #
UnitsTotal MCA Volt/phase
Condensing Unit 49 10 490 208/3
BC Controllers 1.08 5 5.4 208/1
Indoor Unit 2.25 50 112.5 208/1
Thru Wall Unit Design• (50) 2 ton wall mounted heat pump units with
4 KW electric backup heatSystem MCA/Unit #
UnitsTotal MCA Volt/phase
Thru the Wall 44 50 2200 208/1
Thru the Wall 35 50 1750 208/3
VAV Design• (4) 25 ton package rooftop units with VAV
boxes with 4 kw electric reheatSystem MCA/Unit #
UnitsTotal MCA Volt/phase
25 ton Package Rooftop Unit
149.2 4 596.8 208/3
VAV Box with 4 KW electric reheat
19.2 50 960 208/1
Chilled Water Design• 100 ton air cooled chiller with (50) 2 ton, 2
pipe fan coils with 4 kw electric heatSystem MCA/Unit #
UnitsTotal MCA Volt/phase
Chiller w/pumping package
489.7 1 489.7 208/3
Fan Coils 19.66 50 983 208/1
Electrical Savings SummarySystem Total MCA- 3 Ph Total MCA- 1 Ph
VRF 490 117.9
Thru the Wall (1 or 3 ph.) 1750 2200
Rooftop VAV 597 960
Chilled water FCU’s 490 983
Renovation Project Challenges
• Limited/Insufficient Electric Service• Adequate space to install systems
Space Saving InstallationSpace Required to deliver 20 tons of CoolingSpace Required to deliver 20 tons of Cooling
Ducted 20 tons40″ x 20″ Supply Duct
Ducted 20 tons30″ Round Supply Duct
11/8″ Liquid11/8″ Gas
3″ CHW supply3″ CHW return
VRF 20 tons
Chilled Water20 tons
Rooftop Equipment Layout
CMWSHP 4-PIPE
VAV
RTU & S/S
80 ton Systems80 ton Systems
Rooftop Equipment Layout
Mechanical Room Not RequiredMechanical Room Not Required
Primary System AttributesZoning Energy Efficiency
Other Application Opportunities• Ductless Systems• Projects requiring fast installation• Projects considering using geothermal equipment • Projects involving phasing/tenant buildout• Chilled water/4 pipe designs (operation flexibility )
Other Discussion Points• Outside Air Introduction
• Dehumidification Control
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Thank you for your time!
Questions?
www.mehvac.com
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