Trane MWC507, Руководство по установке и эксплуатации, Страница: 16 / 30

Installation of refrigerant pipe
Purging: •
Sustain the liquid pipe of the indoor unit with the insulating material in the hand. a.
When it is incapable to resist due to change of pressure, remove the insulating material b.
quickly, and make the nitrogen blow off fast from the pipe mouth (fi rst purging).
Then resist the pipe mouth with the insulating material (second purging).
c.
Place a piece of clean cloth in front of the mouth, the nitrogen is ejected onto the cloth, and d.
dirt contained in the high-speed nitrogen is found. If the cloth becomes wet, it indicates that
water exists in the pipe. Repeat purging till no dirt is blown off and the cloth does not be
wet.
For indoor unit B, repeat the above mentioned operation. •
After fi nishing working on the liquid pipe, carry out the aforesaid purging for the gas pipes. •
Leakage detection and heat insulation of refrigerant pipe
After construction of the fi tting pipe fi nishes, a tightness test should be applied to the whole •
refrigerating system (indoor unit and pipe). Fill the nitrogen to a specifi c pressure (R410A model
– 38 Kgf/cm
2
) simultaneously from both sides of the gas and liquid pipes, view whether there is
change of pressure, check whether each interface (welding or fl ared) and the whole system have
good tightness, and see if there have leakage sources.
Caution: when the air temperature at the time of pressurization is different from that at the time
•
of observation, correction should be carried out according to the following equation:
Actual value = Pressure at the time of pressuri (Temperature at the time of pressurization
•
– Temperature at the time of observation) ġ 0.1 Kgf/cm
2
If no gas leakage is detected, insulate the fi tting pipe with heat insulating material. The gas pipe •
and liquid pipe need insulating respectively.
Surface
wrapping tap
Control
cable
No heat
insulation
for the joint
Heat
insulation
● The gas pipe and
liquid pipe should
not be insulated
together
● Coupling portion
of the fitting pipe
should be
insulated
completely
● Only the gas pipe
is insulated
(cooling only) ● Both the gas pipe
and liquid pipe are
insulated ● Insulated support
Incorrect
Liquid pipe
Gas pipe
Liquid pipe
Control
cable
Surface
wrapping
tap
Gas pipe
Heat
insulation
Copper tube
Arc gasket
Metal
support
Heat
insulation
Heat
insulation
Heat insulation
Surface
wrapping tap
Gas
pipe
Liquid
pipe
Correct
Control
cable
For more requirements of lines, please refer to the Installation, Operation and Maintenance Manual of
outdoor unit.
16 AMS-SVX04A-EN