Panasonic U-4LE1E5 / U-4LE1E8 / U-5LE1E5 / U-5LE1E8 / U-6LE1E5 / U-6LE1E8 (serv.man2) Service Manual ▷ View online
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1. Precautions on Renewal Design & Installation
Renewal
3. VRF Renewal Kit with High-pressure SW Kit and Sight Glass
The following shows an overview of the VRF Renewal Kit (CZ-SLK2) that is required when existing tubing is reused.
If the exact tube length and tube size of the existing tubing are uncertain, attach a sight glass in accordance with
the figure below. It will be used for checking the amount of additional refrigerant charge (calculating the amount in
Judgment 4).
If the exact tube length and tube size of the existing tubing are uncertain, attach a sight glass in accordance with
the figure below. It will be used for checking the amount of additional refrigerant charge (calculating the amount in
Judgment 4).
VRF Renewal Kit: CZ-SLK2
NOTE
If the tube size does not match that of the existing tubing, use a reducer (field supply) to adjust the tube diameter.
Attaching the VRF Renewal Kit, sight glass and High-pressure SW Kit
VRF Renewal Kit (CZ-SLK2) shall be attached to the liquid tubing of all outdoor units.
VRF Renewal Kit (CZ-SLK2)
There is no need to remove the VRF Renewal Kit (CZ-SLK2) after a test run is performed because normal
operation is possible while it is attached.
operation is possible while it is attached.
When attaching the VRF Renewal Kit (CZ-SLK2), care shall be taken with regards to the installation location
and orientation of the filter drier and ball valve. If a mistake is made, the refrigerant in the system needs to be
recovered when the filter drier is replaced, which will make maintenance difficult.
and orientation of the filter drier and ball valve. If a mistake is made, the refrigerant in the system needs to be
recovered when the filter drier is replaced, which will make maintenance difficult.
Thermal insulation material (field supply: heat resistance of 80°C or higher and thickness of 10 mm or greater)
shall be applied to the VRF Renewal Kit (CZ-SLK2).
shall be applied to the VRF Renewal Kit (CZ-SLK2).
The filter drier of the VRF Renewal Kit (CZ-SLK2) may need to be replaced depending on the condition of the
existing unit. Use a Danfoss DMB 164 as the replacement filter drier.
existing unit. Use a Danfoss DMB 164 as the replacement filter drier.
•
High-pressure SW Kit (CZ-PSWK2 or CZ-PSWH2) shall be attached to both liquid and gas tubing of all outdoor
units.
units.
•
•
•
•
•
B
A
A
B
Outdoor unit side
Filter Drier
Charge Port
Indoor unit side
Unit : mm
445 (12, 14, 16HP)
535 (8, 10HP)
Connecting tube dimensions
A : ø12.7 (12, 14, 16HP)
B : ø9.52 (8, 10HP)
B : ø9.52 (8, 10HP)
B
A
A
B
Outdoor unit side
Filter Drier
Charge Port
Indoor unit side
Unit : mm
445 (12, 14, 16HP)
535 (8, 10HP)
Connecting tube dimensions
A : ø12.7 (12, 14, 16HP)
B : ø9.52 (8, 10HP)
B : ø9.52 (8, 10HP)
Liquid tubing
Sight glass (field supply)
If the exact tube length and tube size
of the existing tubing are uncertain,
attach a sight glass to the liquid
tubing, and use it to check whether
there is an appropriate amount of
additional refrigerant charge.
If the exact tube length and tube size
of the existing tubing are uncertain,
attach a sight glass to the liquid
tubing, and use it to check whether
there is an appropriate amount of
additional refrigerant charge.
Balance tubing
Gas tubing
CZ-PSWH2
(for 3WAY VRF)
(for 3WAY VRF)
High-pressure SW Kit
CZ-PSWK2
(for 2WAY and MINI VRF)
(for 2WAY and MINI VRF)
Outdoor
unit
Outdoor
unit
Outdoor
unit
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Renewal
1. Precautions on Renewal Design & Installation
4. Procedure for Renewal
After checking "2. Basic Points for Using Existing Tubing," perform the work in accordance with the renewal flow
below. When performing the work, also check the "DESIGN of VRF SYSTEM" section.
below. When performing the work, also check the "DESIGN of VRF SYSTEM" section.
Renewal flow
Judgment 1:
Judgment 2:
Judgment 2:
Is the existing tubing reusable as refrigerant tubing?
Are the tubing length and installation height
difference of the existing tubing within the
tolerance ranges of the new system?
Are the tubing length and installation height
difference of the existing tubing within the
tolerance ranges of the new system?
Judgment 3:
Judgment 4:
Is the existing tubing within the ranges of reusable
tube size?
Is the additional refrigerant charge at or below the
upper limit?
tube size?
Is the additional refrigerant charge at or below the
upper limit?
Can existing tubing
be reused?
New tubing needs
to be installed.
to be installed.
Impossible to reuse
No problem with Judgments 1 to 4
Recover refrigerant
with refrigerant
recovery machine
with refrigerant
recovery machine
Cooling is
not possible.
not possible.
Can the existing unit perform
the cooling operation?
Perform the cooling operation for at least 15 minutes, and then perform
a pump down to recover refrigerant in the existing unit.
a pump down to recover refrigerant in the existing unit.
Yes
Remove the existing indoor and outdoor units
Is there a problem with dirt
inside the existing tubing?
Judgment 5
There is dirt applicable
to Judgment 5.
to Judgment 5.
Install the new indoor and outdoor units, and attach the VRF Renewal Kit (CZ-SLK2) and High-pressure
SW Kit (CZ-PSWH2 or CZ-PSWK2).
If the exact length and the like of existing tubing are uncertain, attach a sight glass.
If the gas tube size of the main tubing is three sizes larger, add oil. (Judgment 3 item)
SW Kit (CZ-PSWH2 or CZ-PSWK2).
If the exact length and the like of existing tubing are uncertain, attach a sight glass.
If the gas tube size of the main tubing is three sizes larger, add oil. (Judgment 3 item)
Perform an air-tightness test, air purge, and refrigerant charge.
If the exact tube length and tube size are uncertain, charge with the minimum amount of additional
refrigerant that was calculated in Judgment 4 for the case in which the amount of additional refrigerant
charge becomes the least. Furthermore, determine whether the minimum amount of additional
refrigerant charge resulted in an appropriate amount of refrigerant charge for the whole system when
you perform a cooling test run, and make adjustments to the amount of refrigerant as necessary.
refrigerant that was calculated in Judgment 4 for the case in which the amount of additional refrigerant
charge becomes the least. Furthermore, determine whether the minimum amount of additional
refrigerant charge resulted in an appropriate amount of refrigerant charge for the whole system when
you perform a cooling test run, and make adjustments to the amount of refrigerant as necessary.
Is there any history
of a failure of the compressor in
the existing unit?
Could the existing
unit perform the cooling
operation?
Recheck
Recheck
Failure
Cooling was
not possible.
not possible.
Perform a heating test run.
(1)
(1)
(2)
Operate in the heating test run mode for 30
minutes.
Replace the filter driers of all outdoor units.
minutes.
Replace the filter driers of all outdoor units.
* Obtain replacement filter driers separately.
No
Yes
Perform a cooling test run.
If the minimum amount of additional refrigerant was added when the exact exist tube length and the like were
uncertain, check the condition of flowing refrigerant through the sight glass attached to the liquid tubing, and
add refrigerant to adjust the amount of refrigerant if insufficient amount of refrigerant level is detected.
However, the amount of additional refrigerant charge shall not exceed the maximum level.
uncertain, check the condition of flowing refrigerant through the sight glass attached to the liquid tubing, and
add refrigerant to adjust the amount of refrigerant if insufficient amount of refrigerant level is detected.
However, the amount of additional refrigerant charge shall not exceed the maximum level.
No problem
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1. Precautions on Renewal Design & Installation
Renewal
5. Judging Whether Possible to Reuse Existing Tubing: Judgments 1 to 5
It is necessary to check whether the existing tubing satisfies the following Judgments 1 to 5 while referring to the
figure below. If the existing tubing does not satisfy the following conditions, new tubing needs to be installed.
figure below. If the existing tubing does not satisfy the following conditions, new tubing needs to be installed.
Main tube
*1
[1]
Main tube after branch
*1
[2][3][4]
Indoor unit connection tube
[5][6][7][8][9]
*1: If a main tube after a branch is the same size as the main tubing, it shall be considered to be a main tubing.
For example, if the tube size of [3] is the same as the tube size of [1], the main tubing is [1] + [3].
Judgment 1
Is the refrigerant tubing reusable?
Is the refrigerant tubing reusable?
Check whether the existing refrigerant tubing is reusable (the refrigerant tubing is for R22 or has the same or
a higher design pressure than refrigerant tubing for R22). Table 8-1 shows the thickness of reusable refrigerant
tubing. Also check the maximum working pressure for branches separately.
a higher design pressure than refrigerant tubing for R22). Table 8-1 shows the thickness of reusable refrigerant
tubing. Also check the maximum working pressure for branches separately.
Table 8-1 Usable Refrigerant Tubing (JIS B 8607)
Outer dia. (mm)
6.35
9.52
12.7 15.88 19.05 19.05 22.22 25.4 28.58 31.75 38.1 41.28 44.45 50.8
Thickness (mm)
0.80
0.80
0.80
1.00
1.00
1.00
1.00
1.00
1.00
1.10
1.15
1.20
1.25
1.40
Judgment 2
Are the tubing length and installation height difference of the existing tubing within the tolerance ranges
of the new system?
Are the tubing length and installation height difference of the existing tubing within the tolerance ranges
of the new system?
The refrigerant tubing length and installation height difference must be within the tolerance ranges of the tubing
length and installation height difference of the new system.
length and installation height difference of the new system.
[1]
[2]
[3]
[5]
[6]
[4]
[7]
[8]
[9]
[1]
[2]
[3]
[5]
[6]
[4]
[7]
[8]
[9]
Sample Image of Tubing of Existing Unit
Indoor unit A
Indoor unit B
Indoor unit C
Indoor unit D
Indoor unit E
First branch
Fig. 8-1
Outdoor
unit
Applicable Tubing
Item
1 /2 H, H Material
O Material
Material
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Renewal
1. Precautions on Renewal Design & Installation
Judgment 3
Is the existing tubing within the reusable tube size ranges?
Check whether the tube sizes of the existing refrigerant tubing are within the usable ranges.
Tables 8-2 to 8-4 show the usable tube size ranges for each of the main tubing, main tubing after branches, and
indoor unit connection tubing.
The existing tube sizes must be checked to determine whether they are within the ranges in these tables.
Furthermore, extra oil may need to be added depending on the gas tube sizes of the main tubing.
Tables 8-2 to 8-4 show the usable tube size ranges for each of the main tubing, main tubing after branches, and
indoor unit connection tubing.
The existing tube sizes must be checked to determine whether they are within the ranges in these tables.
Furthermore, extra oil may need to be added depending on the gas tube sizes of the main tubing.
Table 8-2 Usable Tube Size Ranges for Main Tubing [1]
Outdoor Unit
HP
Gas Tube (mm)
Liquid Tube (mm)
Normal
*2
Usable Range
Normal
*2
Usable Range
4 HP
15.88
19.05
9.52
9.52 to 12.7
5 HP
15.88
19.05
9.52
9.52 to 12.7
6 HP
19.05
19.05
9.52
9.52 to 12.7
8 HP
19.05
19.05 to 28.58
*1
9.52
9.52 to 25.4
10 HP
22.22
22.22 to 31.75
*1
9.52
9.52 to 25.4
12 HP
25.4
25.4 to 38.1
*1
12.7
12.7 to
25.4
14 HP
25.4
25.4 to 38.1
*1
12.7
12.7 to
25.4
16 HP
28.58
28.58 to 41.28
*1
12.7
12.7 to
25.4
18 HP
28.58
28.58 to 41.28
*1
15.88
15.88 to 25.4
20 HP
28.58
28.58 to 41.28
*1
15.88
15.88 to 25.4
22 HP
28.58
28.58 to 41.28
*1
15.88
15.88 to 25.4
24 HP
28.58
28.58 to 41.28
*1
15.88
15.88 to 25.4
26 HP
31.75
31.75 to 44.45
*1
19.05
19.05 to 25.4
28 HP
31.75
31.75 to 44.45
*1
19.05
19.05 to 25.4
30 HP
31.75
31.75 to 44.45
*1
19.05
19.05 to 25.4
32 HP
31.75
31.75 to 44.45
*1
19.05
19.05 to 25.4
34 HP
31.75
31.75 to 44.45
*1
19.05
19.05 to 25.4
36 HP
38.1
38.1 to 50.8
*1
19.05
19.05 to 25.4
38 HP
38.1
38.1 to 50.8
*1
19.05
19.05 to 25.4
40 HP
38.1
38.1 to 50.8
*1
19.05
19.05 to 25.4
42 HP
38.1
38.1 to 50.8
*1
19.05
19.05 to 25.4
44 HP
38.1
38.1 to 50.8
*1
19.05
19.05 to 25.4
46 HP
38.1
38.1 to 50.8
*1
19.05
19.05 to 25.4
48 HP
38.1
38.1 to 50.8
*1
19.05
19.05 to 25.4
Table 8-3 Usable Tube Size Ranges for Main Tubing after Branches [2][3][4]
Capacity after Branch
*3
(kW)
Gas Tube (mm)
Liquid Tube (mm)
Up
to
7.0
12.7
to
15.88
9.52
to
9.52
7.1
to
8.9
15.88
to
15.88
9.52
to
9.52
9.0
to
16.0
15.88
to
19.05
9.52
to
9.52
16.1
to
22.4
19.05
to
28.58
9.52
to
12.7
22.5
to
29.9
22.22
to
28.58
9.52
to
12.7
30.0 to 41.9
25.4 to 31.75 12.7 to 15.88
42.0 to 52.3
28.58 to 38.1
12.7 to 15.88
52.4 to 69.9
28.58 to 41.28 15.88 to 19.05
70.0 to 97.9
31.75 to 44.45 19.05 to 22.22
98.0 to 105.9
38.1 to 44.45 19.05 to 22.22
From 106.0
38.1 to 50.8
19.05 to 25.4
*1: If the gas tube size of the main
tubing is three sizes larger than
the normal tube size, oil needs to
be added. Add 30 cc of oil for each
meter of main tubing.
the normal tube size, oil needs to
be added. Add 30 cc of oil for each
meter of main tubing.
*2: If the main tubing is the same or
smaller than the normal tube size,
the size needs to be increased.
the size needs to be increased.
• If the maximum tube length exceeds
90 m, increase the size of the gas
tubing and liquid tubing to one size
larger than the normal tube size.
tubing and liquid tubing to one size
larger than the normal tube size.
• If the maximum length of the main
tubing exceeds 50 m, increase the
size of just 50 m of only the gas
tubing of the main tubing to one size
larger than the normal tube size.
size of just 50 m of only the gas
tubing of the main tubing to one size
larger than the normal tube size.
*3: How to calculate the capacity after
branches
The capacity after a branch is the total
capacity of all indoor units connected
downstream of that branch.
The following table shows examples of
calculating the capacity after branches
for the case of Fig.8-1.
The capacity after a branch is the total
capacity of all indoor units connected
downstream of that branch.
The following table shows examples of
calculating the capacity after branches
for the case of Fig.8-1.
Main Tubing
after Branches
Capacity after Branches
[2]
Total capacity of A+B
[3]
Total capacity of C+D+E
[4]
Total capacity of D+E
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