McQuay MDS080B R - Page 18

©2005 McQuay International
17
Outdoor
Oil trap
(every 6~8m fall of the
gas pipe set a oil trap)
Indoor
● Limitation of the refrigerant piping length:
MDS080~320 TUBE PIPING
Total length Actual Length
≤ 350m
L1+L2+...+Li+a+b+…+i
Actual Length
≤ 125m
Max length
Equivalent length
≤ 150m
L1+L2+... +Li+i
Length
of
tube
Equivalent length from the 1
st
bifurcation
to longest piping
≤ 40 m
L2+L3+...+Li+i
Outdoor is in high position
≤ 50 m
-
Indoor and
outdoor
Indoor is in high position
≤ 40 m
-
Height
difference
Between indoors
≤ 15 m
-
Note:1) When outdoor units is above the indoors units, every 6 ～ 8m fall of the gas pipe shall set a oil trap;
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 ╳ equivalent length for elbow + number of trap ╳ equivalent length for trap
For bifurcation, the equivalent length is 0.5m, branch piping 1.0m, elbow and oil trap ‘s equivalent as following table:
Equivalent length Equivalent length
DIA.
Elbow (m ）
Oil trap (m)
DIA.
elbow (m ）
Oil trap (m)
φ 9.52
0.18 1.3
φ 28.6
0.50 3.7
φ 12.7
0.20 1.5
φ 31.8
0.55 4.0
φ 15.88
0.25 2.0
φ 34.9
0.60 4.4
φ 19.05
0.35 2.4
φ 38.1
0.65 4.7
φ 22.23
0.40 3.0
φ 41.3
0.70 5.0
φ 25.4
0.45 3.4
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:
Fiberglass ＋ Steel
Insulation Material
Adhering material ＋ Chloroethylene foam ＋ adhering strip
Indoor Chloroethylene insulation strip
Bare floor
Water proof flax ＋ Bronze Pitch
Layer
outdoor
Water proof flax ＋ galvanized panel ＋ painting
● Gas and liquid insulation
installation as shown as right:
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Bifurcation
L1
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L2 L4
L3
b c d
L5
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Li