McQuay MDS080B R Installation Manual page 18

● Limitation of the refrigerant piping length:
L1
L2
Total length
Length
Max length
of
tube
Equivalent length from the 1
to longest piping
Indoor and
Height
outdoor
difference
Between indoors
Note:1) When outdoor units is above the indoors units, every 6
2) Equivalent length is the length to consider and deduct the turning pressure drip and tube pressure drop ;
Equivalent length =Actual length + number of elbow
For bifurcation, the equivalent length is 0.5m, branch piping 1.0m, elbow and oil trap 's equivalent as following table:
DIA.
Elbow (m ）
φ 9.52
0.18
φ 12.7
0.20
φ 15.88
0.25
φ 19.05
0.35
φ 22.23
0.40
φ 25.4
0.45
7． ． ． ． 4 Insulation of refrigerant piping:
To apply the enough thickness of the insulation material to wrap the liquid and gas piping, no leakage of condensing water allowed;
● Insulation material specification as following table:
Insulation Material
Layer
● Gas and liquid insulation
installation as shown as right:
Bifurcation
L3
L4
a b
Actual Length
Actual Length
Equivalent length
st
bifurcation
Outdoor is in high position
Indoor is in high position
equivalent length for elbow + number of trap
╳
Equivalent length
Oil trap (m)
1.3
1.5
2.0
2.4
3.0
3.4
Adhering material ＋ Chloroethylene foam ＋ adhering strip
Indoor
Bare floor
outdoor
L5 Li
e
c d
MDS080~320 TUBE PIPING
≤ 350m
L1+L2+...+Li+a+b+...+i
≤ 125m
L1+L2+... +Li+i
≤ 150m
≤ 40 m
L2+L3+...+Li+i
≤ 50 m
≤ 40 m
≤ 15 m
～ 8m fall of the gas pipe shall set a oil trap;
DIA.
φ 28.6
φ 31.8
φ 34.9
φ 38.1
φ 41.3
Fiberglass ＋ Steel
Chloroethylene insulation strip
Water proof flax ＋ Bronze Pitch
Water proof flax ＋ galvanized panel ＋ painting
i
-
-
-
Indoor
equivalent length for trap
╳
Equivalent length
elbow (m ）
Oil trap (m)
0.50
0.55
0.60
0.65
0.70
©2005 McQuay International
17
Outdoor
Oil trap
(every 6~8m fall of the
gas pipe set a oil trap)
3.7
4.0
4.4
4.7
5.0