Air Source Screw Water Chiller Unit – Installation Operation and Maintenance Manual
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6
.3.2 Installation Requirements for the Pipe Connection Between Outdoor Units
and Indoor Units (Supplementary)
6
.3.2.1 Basic Piping Requirements
Operation processes are as follows:
Specify pipe route and dimensions based on the construction drawing
Prepare and install the pipe
supports, hangers, and brackets
Prepare and place the pipe components
Perform
nitrogen
protection
Braze
Clean pipes
Test the air tightness
Seal the pipes with insulation
materials
Perform vacuum drying
6
.3.2.2 Piping Principles for Refrigerants
Item
Cause
Handling Procedure
Imprecise
welding\Unqualified joint
seal\Edge leakage
Gas
tightness
Dryness
Cleanness
Meteoric water
ingress\Engineering water
ingress\Condensate water
generated in the pipe
Products of oxidation in
the pipe during welding,
dust, and foreign matters
Standardize the processing
of auxiliary pipes.
Blast
Vacuum
Introduce nitrogen when
welding.
Keep clean in processing the auxiliary pipes.
Blast
Use qualif ied welding rods.
Strictly follow the welding operation
specif ication.
Strictly follow the interface operation
specif ication.
Gas tightness test
6
.3.2.3 Horizontal Pipe Fixing
Refrigerant pipes may be deformed during the operation of air conditioners. For example, the length and
direction of pipes may change. Hangers or brackets can be used to support the pipes. The installation
instruction is shown in the following table.
Pipe Diameter (mm)
<
Φ
60
Φ
60-80
>
Φ
80
Distance Between Points of Support (m) 3
3.5
4
Typically, the gas pipe and liquid pipe must be suspended in parallel. The distance between points of
support is determined based on the diameter of the gas pipe. The temperature of flowing refrigerant varies
with the unit's operation and working status, and the refrigerant pipe expands when heated and contracts
when cooled. Therefore, proper spaces must be left for the pipes after thermal insulation measures are
taken. Otherwise, copper pipes may break due to stress concentration.
6
.3.2.4 Riser (Vertical Pipe) Fastening
