Wittichen Supply Co.

Progressive Energy, Environment & Sustainability Summit
Chicago
September 11 - 13, 2011
Extreme Efficiency:
Variable Capacity Air Conditioning Systems
Mark T. Kuntz
mkuntz@hvac.mea.com
630-562-9272
Topics
Variable Capacity vs. conventional HVAC
Residential, Multizone & Commercial Systems
Cold climate heating capabilities
EPRI VRF field test program
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Variable Capacity =
“Ductless”, “Mini-Split”, etc.
33-7/16
inches
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3
Variable Capacity versus Conventional
Little or no ductwork = minimizes duct leakage
Individual room control
Extremely quiet
Fast and easy to install and service
Exceptional energy efficiency
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Variable Capacity versus Conventional
 INVERTER Compressor Advantages
 Over-sizing not an issue!
 Output matches load requirements
 Comfort levels are reached quickly
 Extremely low sound levels from both fan and
compressor
 Constant circulation of conditioned air
 Improves humidity control
 Reduces hot/cold pockets
 Warm air delivery at start up in heating mode
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DC Compressor
Indoor Comfort Flexibility
Wall-mounted unit
66
Ceiling-suspended unit
Floor standing unit
Indoor Comfort Flexibility
4-way large
cassette
4-way small
cassette
1-way cassette
77
Indoor Comfort Flexibility
Medium static ducted unit
High static ducted unit
88
Low-profile ducted unit
Vertical ducted unit
Residential Multizone Solutions
 2 to 8 indoor units
 20,000 – 48,000 BTUH
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Commercial Multizone Solutions:
Variable Refrigerant Flow (VRF)
Simultaneous cooling and heating
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Space Savings
Space Required to Deliver 20 tons of Cooling
VRF 20 tons
Ducted 20 tons
30″ Round Supply Duct
11/8″ Liquid
11/8″ Gas
Chilled Water
20 tons
3″ CHW supply
3″ CHW return
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Ducted 20 tons
40″ x 20″ Supply Duct
Equipment Weight Savings
Average equipment weight per ton is 70 lbs
per ton (outdoor unit only)
Average equipment weight per ton for watercooled chiller is 101 lbs./ton
31% reduction in equipment weight
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Installation Flexibility
Water Cooled
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Air Cooled
Installation Flexibility
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VRF and Existing Buildings
• Less intrusive to existing architecture
• Small refrigerant piping instead of large ductwork
• Outdoor installation flexibility
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Utilizing VRF with LEED
 Energy and
Atmosphere: VRF Can
achieve up to 21 points
 Environmental Quality:
VRF can achieve up to
seven points
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LEED NC 3.0
 Certified: 40-49 points
 Silver: 50-59 points
 Gold: 60-79 points
 Platinum: 80 + points
VRF Systems and Energy Modeling
• Energy usage and cost for
the VRF systems can be
modeled using EnergyPro
EnergyPro uses DOE2.1e to
model and compare VRF to
other HVAC system
• EnergyPro is approved for
use with LEED EAc1
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Cold Climate Heating: Hyper Heat
 System re-collects heat
energy that is normally
wasted at the outdoor
coil.
 Process cools the
compressor, allowing
higher speeds at lower
outdoor temperatures.
 Provides full heating
capacity and
comfortable discharge
air temperatures at low
outdoor temperatures.
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Cold Climate Heating: Hyper Heat
120
100
100% @ 5o F
80
87% @ -4o F
60
80% @ -13o F
40
20
0
-13
-4
0
5
10
17
25
30
35
40
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Mitsubishi Electric Hyper-heat INVERTER (H2iTM)
Mitsubishi Electric Standard INVERTER Heat Pump system
Typical Unitary Equipment
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EPRI Energy Efficiency Demonstration
-VRF Installations
Operating Site
Planned Site
20
4'
Faith Academy—Mobile, AL Instrumentation Schematic
4'
31'
ModHopper
ROOM 1
ROOM 2
ROOM 3
ROOM 4
120 VAC
above ceiling
ROOM 5
ROOM 7
ROOM 6
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ROOM 8
POWER
41
32'
2, 18
1, 17
4, 20
3, 19
5, 21
6, 22
7, 23
8, 24
15'
Building
2Control
CAT-5 (1 pair)
Power
42
GIRLS
BOYS
GIRLS
33
34
35
36
37
38
Enclosure
39
Flow
VRF
24vdc
Power
Supply
Flex I/O
271'-0"
4'
BOYS
120 VAC
120 VAC
above ceiling
46
31'
POWER
ROOM 9
ROOM 10
ROOM 11
ROOM 12
ROOM 13
43
BAPI wireless Temp.
and RH Transmittor
32'
45
9, 25
10, 26
11, 27
12, 28
15'
ROOM 16
Belden 8451 Signal Wire
6
15, 31
14, 30
Static IP Address
BOYS
Carbon Dioxide
Transmitter
GIRLS
271'-0"
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ROOM 15
ROOM 14
13, 29
Building
3 - VRF
GIRLS
AS
Data Log.
31'-11 15/16"
4'
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Figure 1—Field Test Layout
BOYS
16, 32
Figure 3—Indoor Ceiling Cassette
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Figure 2—24 Ton VRF Outdoor Unit
Refrigerant Flow Meter
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Table 1--VRF Performance at Mobile, AL
-Monthly Energy Summaries, 2010
April
September
Base Total Energy:
VRF Total Energy:
Savings (Base – VRF):
690kWh
469kWh
221kWh
Base Total Energy:
VRF Total Energy:
Savings (Base – VRF):
4848kWh
2812kWh
2036kWh
% difference
-32%
% difference
-42%
October
May
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Base Total Energy:
VRF Total Energy:
Savings (Base – VRF):
3618kWh
2351kWh
1266kWh
Base Total Energy:
VRF Total Energy:
Savings (Base – VRF):
2928kWh
1607kWh
1322kWh
% difference
-35%
% difference
-45%
Figure 4—Power Profiles for September 17, 2010
95
40
Outdoor Temperature
90
Indoor Average Temperature
35
VRF Hour Average Power
Baseline Hour Average Power
30
80
25
75
20
70
15
65
10
60
5
55
0
12:00 AM
3:00 AM
6:00 AM
9:00 AM
12:00 PM
Time
25
3:00 PM
6:00 PM
9:00 PM
12:00 AM
Power (kW)
Temperature (F)
85
Re-Cap: Benefits of Variable Capacity
Systems
Space Utilization
 Installation flexibility to meet building space requirements
 Minimal impact to existing building architecture and structure
Occupant Comfort




Individual comfort control
Indoor unit flexibility to meet the needs of any space
Meets occupant ventilation air requirements
Quiet operation
Energy Savings
 Inverter driven compressor
 No wasted heat; cold climate capable
 Meets requirements for LEED points
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Thank you for your time!
Questions?
www.mehvac.com
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