1. INVERTER VRF COMMERCIAL A/C
WESTPOINT Commercial Air conditioners
INVERTER VRF COMMERCIAL A/C

2. Contents 1 2 3 4 What’s WMV & VRF? Residential central air AC
WMV energy consumption analysis 4
Digital scroll VS Inverter

3. Part ⅠGMV & VRF Variable Refrigerant Flow Review of VRF(VRV)
Developing from traditional split type air conditioner.
Consist of outdoor units, indoor units, Refnet, controller etc.
One outdoor unit can drive at least 16 indoor units, with which different capacity and appearance.
Applied intensively in office building, hotel, high grade department, villa etc.

4. WMV W– WESTPOINT M – Multi-connected (Max. 1:32) V – VRF system
Introduction of GMV
W– WESTPOINT
M – Multi-connected (Max. 1:32)
V – VRF system
WMV

5. 2 ways to achieve VRV VRV Inverter Digital scroll Rotor
Originating from Japan, frequency conversion;
Electrical adjustment;
Digital scroll
Technology from Copeland;
Mechanic adjustment;
Rotor
Reluctance motor

6. E.G. WMV in office building
Combination
with
Outdoor fresh
air processor

7. Part ⅡResidential central air conditioner
When central AC enter residential area…
Virtues of Central Air Conditioner
Central air conditioner-centralized processing、distributing；
Baring comparatively higher EER, more energy saving;
Residential Central Air Conditioner
More comfortable, lower noise, less vibration, more accurate adjustment;
Types of residential central AC
Duct type
Mini chiller
WMV

8. Family of residential central AC
1. Duct type
Low initial investment;
Indoor air quality improve by introduction of fresh air
Require enough height to layout the duct;
Individual adjustment for single room not available

9. Mini Chiller-Hydraulic system
All-Water system (water or ethylene alcohol);
Adopt Fan coils as terminals, space saving;
Without fresh air introduction;
Individual control for each room available;

10. E.G. WMV in detached house
Energy-saving;
Low initial investment;
Comfortable & Accurate;
Individual control;

11. Figure: Ratio of VRV application in Japan
60%
32%
Old building redecoration
New facility

12. Part Ⅲ WMV energy saving analysis
New orientation in working concept
Adopting digital scroll compressor
Core factors
Saving energy
Using refrigerant as heat transfer medium
Sophisticated controlling network
Combination with heat recovery processor

13. 1. New orientation in designing concept
Traditional designing base on the most sever outdoor condition.
Peak of EER/COP sets at partial load. (around 40% of the full load)
Ratio of cooling load throughout one year %
Cooling load (%)
Working time (%)
100 1 50 45 75 42 25 12
Data originate: American Society of Heating, Refrigerating and Air-conditioning Engineers. (ASHRAE)

14. 2. Adopt digital scroll compressor
Traditional residential split type AC adopts Rotary type compressor;
The efficiency of Scroll type compressor is higher than Rotary type or Reciprocal type compressor;
Energy consumption can be reduced by 10-15% compared with the reciprocal type at the same capability;
Comparing Items
Scroll type
Rotary type
Reciprocal type
EER
2.9
2.4~2.6
2.2~2.6
Volumetric efficiency
0.99
0.94
0.7
Adiabatic efficiency
0.98
0.93
0.88
Num. of part in compression chamber 1 3 7
Weight ratio
0.8
1.0
Machining precision
1~3
10~30
Output power
1~10
0.4~1

15. Core component of digital scroll
Variable Capacity Adjustment is achieved by PWM (Pulse-Width-Modulation) valve
by-pass pipe
“Fixed Scroll”
Discharge Pipe
Suction Pipe
Loading
Gap: 1mm between two scrolls!
Orbit Scroll
Idling

16. Adjust capability output
Pulse-width: Maintain a balance between Demanding and Providing;
“Digital”: loading-100%(1), while Idling-0%(0), forming the sequence
…..
Cooling Capacity
Digital Multi Unit
Inverter Unit
Capacity Demanded

17. 3. Using refrigerant as heat transfer medium
In GMV, heat transferred via refrigerant directly;
The heat amount transferred can be 10 times of those transferred by water, and 20 times via air.
Comparing: Property of heat transfer medium
Types of medium
Utilized heat
Transfer amount
Energy consumption (transfer 120 kW cool load)
Water
sensible heat
20.1kJ/kg (△t=5℃)
4.8
Air
10.1kJ/kg (△t=10℃)
7.5
Refrigerant
evaporating latent heat
206kJ/kg
2.6
Power
Consumption
54% of those transfer via water;
35% of those transfer via air;

18. 4. Sophisticated intelligent controlling
Controlling Object
Forming the network
Sensors (temperature, pressure);
Throttling devices (electrical expansion valves, pore plates);
Advanced logical algorism;
Basic principle
Providing=Demanding

19. 5. Combination with heat recovery processor
To improve the IAQ, people can open the windows sometimes, or install a ventilating fan connect to outside;
But cooling load would rise, and unfiltered air with instable and unreliable factor would penetrate in.
The Fresh Air Heat-Recovery System can solve this problem
Introduce more filtered fresh air into the room;
Recycle heat or cooling; (efficiency 75%)
Reduce the amount of poisonous released from the building material;

20. The air route inside the system
1. Excellent water absorbability
exchanging efficiency reaches 75%;
2. Super fire-retardant
Safe and reliable
3. Mildew-proof, clean & healthy.
Structure of
Heat exchanger
Returning air of indoor
Exhaust air
Suction of outdoor air
Cooled fresh air introduced in
Compared to traditional way of ventilation, Fresh air processor reduces 28% of energy consumption!

21. Part Ⅳ Digital scroll VS Inverter
Comparing items
Digital scroll
Inverter
Capability
adjustment
SEER
Electromagnetic interference
Can be omitted
Sever disturbance, expensive electromagnetic-proof apparatus must be installed;
Capacity Shift
Shift to 100% capability immediately
Must have procedure of frequency conversion
By-pass of refrigerant
No need
Have to install
Cooling Capacity
Digital Multi Unit
Inverter Unit
Capacity Demanded
Digital only
Common Inverter comp.
Digital & common parallel connection

22. Summary
WMV can be applied intensively in office building, hotel, luxury department, villa, etc.
Enjoy a high EER/COP under partial load;
Combination with fresh air processor, can improve IAQ & saving energy (up to 30%);
Digital scroll type VRF is more reliable and flexible than Inverter.