This is a presentation regarding the introduction to the heating and cooling system technology called variable refrigerant flow systems. (non-commercial)
3. Began my career in 1986!
About me
24 years as a Mechanical Contractor!
NATE Certified!
Mini-Split Experience since 1995!
VRF Experience since 2007!
Currently: Technical Sales and Support!
4. My Customers are:!
End Users and Building Owners
Contractors
Distributors
Mechanical Engineers
Architects
Factory Sales Personnel
About me
5. 5
Todays Topics
! ! !1. What is VRF Technology?!
! ! !2. What are the Key System Features?!
! ! !3. How Do VRF Systems Work?!
! ! !4. Review of System Components!
! ! !5. Applications and Design!
! ! !6. Service and Maintenance!
16. 16
What is VRF?
A system of singular or modular heat pumps !
and indoor fan coils that are connected !
by a common system control and !
a common set of refrigerant piping.!
!
17. 17
What is VRF?
A system of singular or modular heat pumps !
and indoor fan coils that are connected !
by a common system control and !
a common set of refrigerant piping.!
!
18. 18
What is VRF?
A system of singular or modular heat pumps !
and indoor fan coils that are connected !
by a common system control and !
a common set of refrigerant piping.!
!
19. 19
The refrigerant is passed through a series of !
fan coils by means of variable speed
compressors and metered by an !
electronic expansion valve (EEV) that !
regulates refrigerant flow to !
accommodate the comfort set point !
for individual fan coils and zones!
What is VRF?
20. 20
!
The variable speed compressor increases!
or decreases the system capacity to !
satisfy the individual load requirements!
What is VRF?
21. 21
!
The variable speed compressor increases!
or decreases the system capacity to !
satisfy the individual load requirements!
What is VRF?
Personalized zoned
comfort control
22. 22
!
The software programming in the outdoor unit
continually scans about 250 data points to!
meet specific tolerances in target temperatures
and pressures.!
What is VRF?
the software is a conductor in a
sophisticated symphony
42. Air
30” Diameter
Ductwork
Water
2 1/2” Iron Pipe
2” Iron Pipe
Refrigerant R410A
1 1/8” Copper Pipe
Space required to deliver 20 tons of cooling
Economy of Scale
44. Air
.3 Watts/kg
Water
5.8 Watts/kg
Refrigerant R410A
57 Watts/kg
Economy of Scale
Transporting expensively generated conditioned air
Is probably not the best method to heat and cool a building
Refrigerant has 10x the heat transfer capacity of chilled water and 190x that of air
48. 48
System Automatically Matches the Zone Load
Adjusts the Flow of Refrigerant and Energy
Adjusts the Compressor Speed and Fan Speed
Improves Temperature Control
Energy Efficient
49. 49
off the charts energy efficiency
when in part load conditions
Inverter driven compressor matches
compressor speed to meet
the full or part load demand
soft starts
no lock rotor amps
51. Room
Temperature
Set Point 75F
60Hz
Compressor
0Hz
150Hz
30Hz
Room temperature is steady.
High rotation speed up to 120Hz
Keeps rotation speed low
after temperature stabilizes.
adjusts rotation speed precisely
keeps steady space temperature
80F
ON Very Efficient
Comfortable!Very fast!
Load Matching Refrigerant Flow
“soft start” Low Current at start
56. Typical HVAC Efficiency Ratings
rating systems are based at part load capacity
• IEER – Integrated Energy Efficiency Rating = Took the place of IPLV, is
used for VRF product, and is explained in detail on the next slide
• SCHE – Simultaneous Cooling & Heating Efficiency = the efficiency of
VRF Heat Recovery at simultaneous 50% heating & 50% cooling
59. 59
If installed correctly,!
VRF systems are bullet proof.!
!
-Large Texas Based Commercial Contractor!
“
”
.05% (Five Hundredths of One Percent) Warranty Return
Reliability
61. Lower Life Cycle
the cost of an hvac system is about more than the cost of
design, equipment and installation.
you need to consider operation, service,
maintenance and replacement in the
total cost equation.
VRF zoning systems are more efficient, easier to design,
takes less time to install and require significantly less
maintenance than conventional hvac systems.
65. LEV
Coil Inet
Coil Outlet
Constantly monitoring
to keep a target
Superheat or
Subcooling
Temperature
Return Air Stream Sensor
SMART COIL
or Room Space Sensor
66. LEV
Coil Inlet
Coil Outlet
Constantly monitoring
to keep a TARGET
Superheat or
Subcooling
Temperature
Return Air Stream Sensor
or Room Space Sensor
SMART COIL
70. 70
Two vs Three Pipe Heat Recovery Systems
Inverter+Fixed or Inverter Only
Service Access to Components
Controls Network
Piping Rules
Programming Logic
DIFFERENCES IN VRF SYSTEMS
71. Capacities at Low Ambient Conditions
Defrost Strategy
Oil Management
Customer Support/Training
Service Software Tools
Selection Software Tools
Information Available to the Public
DIFFERENCES IN VRF SYSTEMS
72. 72
Review of System Components
Air and Water Source Heat Pumps
DOAS
ERV
Indoor Fan Coils
Zone Control
Central Control
82. 82
Three Phase Heat Pump!
6~36 Tons!
208~230, 460 Volt!
Inverter Driven Scroll Compressor!
Sound Rating as Low as 48 dB’s!
Connect 50:1!
Connect up to 130%!
Outdoor Units
84. 84
3,4, & 5 Tons!
208~230 Volt, Single Phase!
Inverter Driven Scroll Compressor!
Sound Rating as Low as 49 dB!
Single Phase Heat Pump!
Connect up to 130%!
Connect 8:1!
Outdoor Units
86. Space Mounted Units
High Wall Mounted
Ceiling Suspended
Floor Standing
(PFFY-NRMU for recessed
mounting not shown)
CITY MULTI VRF
87. Four Way 33x33
Ceiling Cassette
Four Way 24x24
Ceiling Cassette
One Way Cassette
CITY MULTI VRF
Ceiling Recessed Cassettes
88. Concealed Ducted Units
Ceiling Concealed
Medium Static Up to
.6 In W.C.
High Static up to
1 In W.C.
Low Profile
Up to .2 In W.C.
Fan Coil
Down/Horizontal Left/
Vertical Ducted
Product Review CITY MULTI VRF
89. Integrated Digital Control System
• 2 Wire DDC System
– 16 GA. Stranded & Shielded
– Daisy Chain Connection
– Non-Polarized
• Customizable Control Scheme
• Integration into BMS & EMS
• Third Party Equipment Control
Controls Network
93. IN
P1P2F1 F2 P1P2F1 F2 P1P2F1 F2
P1P2
F1 F2
P1P2 P1P2
Zone
1
Zone
2
Zone
3
Typical Controls Wiring
94. System Design
Selection Software
• Easy to Use
• Drag & Drop System Components
• Input Project Information
• Output Layout and System Design
Selection Software