Caution In Connecting Pipes - GREE ELECTRIC GUHD09NK3CO Service Manual

Starting the vacuum pump, when the indicator turns to-1 bar, closing the low pressure handle and stopping
vacuumize. Keep for 15 minutes, ensuring the pressure of the vacuum watch remains.
Take out the valve cover of the gas valve together with the liquid valve.
Loosing the cord of liquid valve until the pressure rise to 0 bar.
Dismantle the tube from the cover of the inlet for refrigerant then, tighten the cover.
Loose the valve cord of the gas valve as well as the liquid valve entirely.
Tighten the valve cover of the gas valve and liquid valve so as to check whether leakage occurred.
c. Installation of Protective Layer of Connecting Pipe
To avoid generation of condensate on the connecting pipe and avoid leakage, the big pipe and the small pipe of
the connecting pipe must be covered by thermal insulation materials, be bundled by adhesive tape, and be isolated from
air.
The joint connecting to the indoor unit must be wrapped by thermal insulation material. There shall be no gap
between the connecting pipe joint and the wall of the indoor unit. Refer to Figure 3-1-6.
Figure 3-1-6
Use adhesive tape to bundle the connecting pipe and the cables together. To prevent condensate from
Use thermal insulation tape to wrap the pipes from the bottom of the outdoor unit until the upper end of the pipe
where the pipe enters the wall. When wrapping thermal insulation tape, the later circle of tape must cover half of the
front circle of tape (Figure 3-1-7).
Caution:
After the pipes are wrapped by protective materials, never bend the pipes to form very small angle, and otherwise
the pipes may crack or break.
After the protective work is completed and the pipes are wrapped, use seal material to block the hole in the wall, so
as to prevent rain and wind from entering the room.

3.2 Caution in Connecting Pipes

The layout of connection pipes shall be in reference to the following principles according to site conditions:
Shorten the connection pipe to minimum, preferably within 5m.
Reduce the height difference between indoor and outdoor units as it might be.
Minimize the number of elbows on connection pipe.
If the connection pipe is longer than 20m, it is needed to check if the lubricating oil in the system is enough. Add if
needed.
If the height difference between indoor and outdoor units is over 10m, it is required to install an oil trap every 6
U-Match Series DC
Inverter Service Manual
Figure 3-1-7
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