Limitations On Refrigerant Tubing Length - Panasonic U-16GE2E5 Test Run Manual

2. Limitations on refrigerant tubing length

(1) System tubing
Limitations on refrigerant tubing length
No. 1 branch
Table 1-1 Ranges for Refrigerant Tubing Length and Installation Height Difference
Equivalent Horsepower
Ratio of capacity for indoor unit to
outdoor units
Minimum capacity of indoor units
that can be connected
Maximum number of indoor units
that can be connected (per system)
* The number of indoor units that can be connected when a W-multi outdoor unit is installed by itself is 24 units or
fewer.
Ranges for Refrigerant Tubing Length and Installation Height Difference
Category
Allowable tubing
length
Allowable height
difference
Allowable length
for branched tubing
(header branch)
(*1) If cooling mode is expected to be used when the external temperature is 10°C or below, the maximum length is
30 m.
(*2) The max/min permissible height between indoor units (α) is found by the difference (∆L) between the maximum
length and the minimum length from the fi rst branch.
α=35- ∆L/2 (however, 0≤α≤15)
When T-tee branch tubing is
used (header branch method)
40 cm or less
Used for
expansion
40 cm or less
450 560
16 20
50 – 200%
24
Symbol
L1 Max. allowable tubing length
∆L= Difference between longest and shortest tubing lengths after
(L2 – L4) the No. 1 branch (fi rst branching point)
LM Max. length for main tube (tube with widest diameter)
ℓ1, ℓ2...ℓ48 Max. length for each tube branch
L5 Distance between outdoor units
Max. height difference between
H1
indoor and outdoor units
H2 Max. height difference between indoor units
H3 Max. height difference between outdoor units
Max. length between fi rst T-tee branch (provided by installer)
L3
and the closed tube end
710 850 450×2 450+560
25 30 32 36
50 – Min: Across the system, a minimum outdoor unit capacity of 50%
170% Max: Total capacity of 130% with 2 outdoor units
Type 22 or greater (equivalent to 0.8 horsepower)
48 (A maximum of 24 indoor units can be connected per 1
32
outdoor unit)
Description
If outdoor unit is above
If outdoor unit is below
I - 2
Symbols
Branch tube
(APR purchased separately)
Ball valve (purchased separately)
T-tee (provided by installer)
Closed (pinch) weld
560×2 450+710 560+710
40 41 45
Tubing length (m)
≤170
(equivalent length 200)
≤70
7≤LM≤120
≤30
≤7
≤50
≤35
(*2)
≤α
1
≤2
710×2
50
(*1)