DEKON, one of the professional manufacture and supplier for VRF system in China. Having full DC inverter outdoor unit and multi selection for indoor units.
6. Indoor unit 2.Hoisting
Use level meter to keep the indoor unit horizontally .
Reduce the running noise
Avoid the condensate water spill from the water collector
Level meter
7. Indoor unit 2.Hoisting
Supports must be strong enough.
The supports should be full thread
booms, and their diameters should
be ≥ 10mm.
Full thread booms
4 Supports
for indoor
unit
8. Indoor unit 2.Hoisting
Dual nuts should be adopted to fix the indoor unit under the ceiling.
Dual nuts Single nut
9. Indoor unit 2.Hoisting
Pack the indoor unit with plastic bag after hoisting to protect them from dust
entering.
11. The outdoor unit should be placed neatly, and reserve enough space for
maintenance.
The outdoor unit should be installed in the place that is dry, well-ventilation
and close to the indoor units .
Outdoor unit 1.Location
13. If 2 rows of ODUs:
Outdoor unit 1.Location
We suggest: face to face
Easy maintenance
No air short-circuit
14. Good duct installation
If the outdoor unit need to side out of the wind by ducting work , it is essential to
remove out the wind grille.
Outdoor unit 1.Location
16. The foundation can be made of channel steel or concrete.
Outdoor unit 2.Foundation making
Reserve the space for discharging condensate water from outdoor units.
17. Rubber anti-vibration pads are necessary to avoid vibration.
Rubber Pads
Outdoor unit 2.Foundation making
19. Piping 0.Pipe storing
For storing the copper pipes:
1. If pipes will be used soon, nozzle should be sealed by plastic bag or tape.
2. If pipes will be stored for a long time, the pipes should be charged into
0.2~0.5MPa Nitrogen and the nozzle should be sealed by welding.
21. Piping 2.Piping check
The permitted length and drop difference
Permitted length Pipe
Pipe
length
Max. pipe length(m
)
Actual length ≤200m
L1+L6+L7+L8+L9+J
Equivalent
length
≤240m
Equivalent length from the first branch
to the farthest indoor unit ≤40m L6+L7+L8+L9+J
Drop
height
Drop height between indoor unit and
outdoor unit ≤110m
——
Drop height between indoor units ≤ 0m3
24. Piping 2.Piping check
LdLcLbLa
LBLA
L1
L6
L2
L7 L8 L9
f g h i j
L3 L4 L5
a b c d e
Height difference between outdoor unit and indoor unit≤ 110m
Height difference between indoor units ≤ 30 m
≤ 110m
≤ 0m3
25. Piping 2.Piping check
Select the correct branch joints according to the installation requirement.
26. Piping 3.Pipe hanging
The distance between the supports of the copper pipes.
When the liquid pipe and gas pipe are hung up together, it is determined by
the diameter of liquid pipe.
Diameter (mm) ≤ 20 20 ~ 40 ≥ 40
Distance (m) 1 1.5 2
Record the actual liquid pipe length for future reference when charging
additional refrigerant.
28. Piping 3.Pipe connection
When install the branch joint horizontally
A
15
°
15
°
A direction
Wrong
Correct
Horizontal
Avoid refrigerant distribution
unbalance.
29. Piping 3.Pipe connection
Keep enough distance:
1. Between two branch joints ≥1m
2. Between branch joints and indoor unit ≥0.5m
3. From the inlet or outlet of branch joint, there should be straight pipe
with length at least 0.5m
0.5m
30. Piping 3.Pipe connection
Why?
If the distance is not big enough, it maybe cause unwanted noise
The distribution of the refrigerant is not well balanced in this case
31. Piping 3.Pipe connection
Two branch joints are too close!
There must be no sharp bend (90ºangle )
within 0.5m away from the branch joint.
32. Piping 3.Pipe connection
Do not replace branch joint with T pipe or use the branch joint from other suppliers
->DEKON branch joint is necessary
33. Piping 3.Pipe connection
Requirement of welding:
When welding the copper pipe, nitrogen is necessary to protect the copper pipe.
The pressure of the nitrogen is 0.02 MPa
Charge the nitrogen to the copper pipe at the beginning of welding and only
when the copper is fully cooled down, the nitrogen can be removed
37. Piping 4.Flushing
Purpose: eliminating dust, water vapor and oxides caused when welding.
Note: the solid can not be eliminated, so please store the pipes carefully to
prevent the solid entering.
Method:
1. Flush the pipe with 0.5 MPa Nitrogen
2. Block all the nozzles of the pipes
3. Use your hand to block one of the nozzles
4. When the pressure is too high to block, then
remove your hand
5. Repeat the step 3 and 4 to each nozzle
6. After flushing, seal all the nozzles
Eliminate
Oxid
es
Mois
ture
Dust
38. Piping 4.Flushing
②
⑥ ⑤ ④ ③ ①
Procedures
From far to near (sequence: ①-②-③-④-⑤-⑥ )
Note
1. When flushing one pipe, the other pipes need to be sealed.
2. After flushing, remember to seal all the pipes.
39. Piping 5.Gas-tightness test
Before test, gas/liquid
stop valves of outdoor
unit should be closed
well
Exhaust the air in the
system by vacuum
pump
Charge Nitrogen
slowly from both gas
and liquid side at the
same time
Purpose: check the gas leakage of the system
Procedures:
Caution: the gas used must be Nitrogen, but Nitrogen is forbidden to charge
to the outdoor unit’s stop valve directly.
40. Piping 5.Gas-tightness test
Sequence of pressure test:
Small leakage check: 4.0
MPa more than 24 hours
3rd stage
Big leakage check: 1.5 MPa
more than 3 minutes
2nd stage
Large leakage check: 0.3
MPa more than 3 minutes
1st stage
41. Piping 6.Insulation
Prevent condensate
water adhere to the
gas pipe
Protect people from
hurt of high temp.
Avoid energy loss.
Purpose:
Caution: After finish the gastight test, we go on the insulation work of the
refrigerant pipe.
42. Piping 6.Insulation
Pipe diameter Thickness
Φ6.4~15.9mm ≥15mm
Φ15.9~38.1mm ≥20mm
Φ38.1~54.1mm ≥25mm
Insulation material
The insulation need to be thicker if the ambient is high temperature and
humidity.
43. The insulation of liquid pipe and gas pipe must be separate
The insulation work must be done to every part of the refrigerant pipes
Piping 6.Insulation
44. Piping 6.Insulation
Wrong Avoid the dust entering the pipe
Block the nozzle of the pipe when crossing the insulation material.
45. Piping 6.Insulation
The gap between two parts should be well insulated by additional insulation
material.
Insulation
Copper pipe
Wrong
46. Piping 7.Vacuum
Purpose:remove the air and water in the system.
Necessary tools:vacuum pump (displacement: 4L/s or more)
Vacuum degree: less than -755mmHg(-0.1MPa)
Caution: Do not open the valves of outdoor unit when vacuuming ,
and Vacuum dry from liquid side and gas side simultaneously
With check
valve
47. Piping 7.Vacuum
Connect to vacuum pump
When vacuum degree reach to
-0.1MPa(-755mmHg) , continue
vacuuming for another 1 hour
Observe whether the pressure changes
or not (more than 1 hour)
Stop vacuuming
Vacuum the system at least 2h
Outdoor unit
OFF OFF
Gas side
Liquid side
Vacuum steps:
48. Additional refrigerant charging procedures:
Note:
1. Charging excessive refrigerant will cause liquid harmer.
2. Record the actual amount of additional refrigerant for further reference.
Piping 8.Charge refrigerant
Calculate necessary amount of additional refrigerant according to
the diameter and length of liquid pipes1
Make sure the gastight test, vacuum dry, pipe installation has
been finished
2
Charge additional refrigerant to the outdoor unit from gas side
according to the calculation result in the 1st step
3
R410A
UP
49. Additional refrigerant charged volume:
Calculate the additional refrigerant according to the diameter and the length
of all liquid pipes connecting to outdoor and indoor units.
Piping 8.Charge refrigerant
Liquid pipe Size
R410A
kg/m
Φ 6.4 0.022
Φ 9.5 0.057
Φ 12.7 0.110
Φ 15.9 0.180
Φ 19.1 0.260
Φ 22.2 0.370
Φ 25.4 0.450
50. Piping 9.Drainage pipe
Condensate water volume (L/h) =
Indoor unit capacity (HP) × 2L/h
Select the diameter
according to the below table
Condensate water volume : V (L/h) I.D (mm) Thickness (mm)
V ≤ 14 Φ 25 3.0
14 < V ≤ 88 Φ 30 3.5
88 < V ≤ 175 Φ 40 4.0
175 < V ≤ 334 Φ 50 4.5
334 < V Φ 80 6.0
Selection steps:
51. Caution:the lean of main drainage pipe must be bigger than 1%
Note
1. If the lean < 1%,then select drainage pipe with bigger diameter
2. The drainage pipe should be independent with other water pipe
3. Never put the drainage pipe together with dirty water pipe
Piping 9.Drainage pipe
Exhaust outlet
Condensate pipe
≥ 1%
52. Piping 9.Drainage pipe
Increase the height
for easy discharge
Discharge with drainage pump:
1. 4-way cassette indoor unit has built-in with drainage pump, its pumping
head is 1200mm at most
2. Drainage trap is not necessary when using the drainage pump
53. Piping 9.Drainage pipe
Note: with drainage pump
Height can not beyond the pump head of drainage pump
Well fixed for this part
56. Piping 9.Drainage pipe
The thickness of insulation material for condensing water pipe is 10mm.
Thin insulation Section of the insulation is too tight
57. Piping 9.Drainage pipe
Water leakage test
Check leakage of water pipe
After finished installation of drainage pipe, filled the pipe with water,
waiting for 24 hours to check whether there’s any leakage.
Check leakage from the indoor unit
Charge water from the check hole of indoor unit to check whether the
water can be exhausted smoothly or not
62. Wiring 2.Power supply
Basic requirement
All wires, and electric devices must
be conformed to local standards
All wiring work must be done by
qualified person
Voltage range:
rated voltage
±10%
Independent
power supply
Capacity of
power device is
bigger enough
Well and
reliable PE line
63. Power supply box
Wiring 2.Power supply
Creepage breaker
/Manual switch
3-Phase
380/400/415V
Power supply for outdoor units
64. Wiring 2.Power supply
Power supply for indoor units
Notice:
All the indoor units which connected to one outdoor system must be connected to
the same power supply
65. Wiring 2.Power supply
Why should all the indoor units which combined in one system have same power
supply?
→ System is normally running.
→ Some indoor units lose power (plug out or power supply failure) .
→ These indoor units stop, but built-in expansion valves still keep former
opening degree, they can’t close.
→ The outdoor units and other indoor units are still running.
→ The liquid refrigerant flow into the stopped indoor units.
→ This unit’s evaporator will freeze, because their fans are stopped .
→ And the other indoor units can not get enough refrigerant distribution, so the
cooling performance drop down.
Even worse, the liquid refrigerant will directly suck back the compressor, which
cause liquid hammer, damage the compressor.
66. Wiring 2.Power supply
Creepage breaker selection
According to 1.5-2 times of the total rated current.
Manual switch selection
As the power is supplied independently, selecting the manual switch and
fuse capacity according to the total capacity.
Total capacity of outdoor units (HP) Manual switch (A) Fuse (A)
10~14 100 75
15~18 100 100
19~28 150 150
29~36 200 200
37~47 300 250
48~50 300 300
52~64 400 400
67. Wiring 2.Power supply
The spec. of the wire is selected
according to the max. total current of
outdoor units
The spec. of the
wire is selected
according to the
max. total current
of indoor units
L N
Indoor unit
Controller
L1L2L3N
68. Wiring 3.Signal wire
Between outdoor units in one combination
Between outdoor unit and indoor unit
A,BA,B
Master unit Slave unitSlave unit
A,B A,B
69. Wiring 3.Signal wire
1. Signal wire should be two core shielded twisted pair
2. Keep away from the strong power
3. Non-polar communication
4. Series connection
Key points
70. Wiring 3.Signal wire
Key points
5.Signal wire and refrigerant pipe should not be tied together.
72. Commission 1.Check before start
Power wire / Signal wire
Refrigerant pipe & insulation
Gastight & vacuum dry
1. All the electric wiring is finished?
2. Wire specification are correct?
3. Power wire are well insulation?
4. Well connection?
Additional refrigerant charge
Check valves
73. Commission 1.Check before start
1. Pipes diameters are correct?
2. Pipes are well insulation?
Power wire / Signal wire
Refrigerant pipe & insulation
Gastight & vacuum dry
Additional refrigerant charge
Check valves
74. Commission 1.Check before start
1. Gastight test has been passed?
2. Vacuum dry has been done?
Power wire / Signal wire
Refrigerant pipe & insulation
Gastight & vacuum dry
Additional refrigerant charge
Check valves
75. Commission 1.Check before start
Refrigerant has been charged correctly?
Power wire / Signal wire
Refrigerant pipe & insulation
Gastight & vacuum dry
Additional refrigerant charge
Check valves
76. Commission 1.Check before start
1. Stop valves of outdoor unit are opened?
2. All the fans rotate normally?
Power wire / Signal wire
Refrigerant pipe & insulation
Gastight & vacuum dry
Additional refrigerant charge
Check valves
78. Commission 2.Check Operation
Check if there’s any error code display
on the IDU or ODU?
Preheat
Error check
Trial operation
Operation test
Hand to user
80. Commission 2.Check Operation
1. Check indoor units:
Preheat
Error check
Trial operation
Operation test
Hand to user
Setting 17℃ in cooling mode
High speed
Running more than 4 hours
Check Temp.
-> Temp. difference between air intake
and outlet of each indoor unit should be
bigger than 8℃。
81. Commission 2.Check Operation
2. Check outdoor unit:
Discharge and suction
temperature of compressors
Pressure of systems
Running current
3. Any abnormal noise, vibration
4. Record the operation parameter
Preheat
Error check
Trial operation
Operation test
Hand over to user
82. Commission 2.Check Operation
System pressure and temperature check
R410A
OD35/-,ID27/19 OD43/-,ID32/23
High pressure (MPa) 2.8~3.0 3.4~3.8
Low pressure (MPa) 0.85~1.0 1.0~1.45
Discharge temp.(℃) 70~80 /
Suction temp.(℃) 11~14 /
Indoor air outlet (℃) 12~15 degree (T1 is around 21~27)
temp. difference
between return and
outlet (ΔT)
8~12
83. Commission 2.Check Operation
Daily operation and maintenance
explanation
Preheat
Error check
Trial operation
Operation test
Hand to user