TCL TCC-09C2HRH/DV, Service Manual, Page: 42 / 75

TCL Air Conditioner Service Manual
42
NOTE : When opening valve stems, turn the hexagonal wrench until it hits against the stopper. DO
NOT try to force the valve to open further.
2.7. 3 Leakage Detection
1).With leakage detection.
Check if there is leakage with leakage detection.
2).With soap water. If leakage detection is not available, please use soap water for leakage
detection. Apply soap water at the suspected position and keep the soap water for more than 3min. If
there are air bubbles coming out of this position, there a leakage.
2.8 Additional Refrigerant Charge
Note:
●
Refrigerant charging must be done after wiring, vacuuming and leak testing.
●
Use electronic scale or fluid infusion apparatus to weight refrigerant to be recharged. Be sure to
avoid extra refrigerant charged, it may cause liquid hammer of the compressor or protections.
●
Charging with mismatched refrigerant can cause an explosion or an accident. Make sure that a
suitable refrigerant is used.
●
The refrigerant container must be opened slowly. Always use guards when charging the system.
●
Do not mix refrigerant types. For R32 refrigerant models, when adding refrigerant to the air
conditioner, ensure the safety of the conditions in the area by controlling flammable materials
●
Always use gloves and glasses to protect your hands and eyes during the charge work.
●
Use supplementing flexible pipe to connect refrigerant cylinder, pressure gauge and outdoor unit.
And The refrigerant should be charged in liquid state. Before recharging, The air in the flexible pipe
and manifold gauge should be exhausted.
●
After finished refrigerant recharge process, check whether there is refrigerant leakage at the
connection joint part.(Using gas leakage detector or soap water to detect).
Some systems require additional refrigerant charge depending on the length of the pipe. The
standard pipe length of this air conditioner is 5 meters (16 feet). The following table can be used to
calculate the additional refrigerant to be charged:
Liquid pipe diameter 6.35(1/4") 9.52(3/8")
12.71(1/2")
Additional charge for 1m/ft (R32)
pipe(R32)
12g/0.13oZ 24g/0.26oZ 40g/0.42oZ
Additional charge for 1m/ft (R410A)
15g/0.16oZ 30g/0.32oZ 65g/0.69oZ
2.9 Engineering of Insulation
2.9.1 Insulation of Refrigerant Pipe
2.9.1.1 Operational Procedure of Refrigerant Pipe Insulation
Cut the suitable pipe
→
insulation (except joint section)
→
flare the pipe
→
piping layout and
connection
→
vacuum drying
→
insulate the joint parts
2.9.1.2 Purpose of Refrigerant Pipe Insulation

During operation, temperature of gas pipe and liquid pipe shall be over-heating or over-cooling
extremely. Therefore, it is necessary to carry out insulation; otherwise it shall debase the performance
of unit and burn compressor.

Gas pipe temperature is very low during cooling. If insulation is not enough, it shall form dew and
cause leakage.

Temperature of gas pipe is very high (generally 50-100
℃
) during heating. Insulation work must
be carried out to prevent hurt by carelessness touching.
2.9.1.3 Insulation Material Selection for Refrigerant Pipe

The burning performance should over 120
℃

According to the local law to choose insulation materials