Lennox LICH4012021T431E-1, Service Manual

Page: 105 / 164

Engineering of insulation
Installation
103
9.
Engineering of insulation
9.1
Insulation of refrigerant pipe
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
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.
9.1.3
Insulation material selection for refrigerant pipe
➢
The burning performance should over 120
℃
➢
According to the local law to choose insulation materials
➢
The thickness of insulation layer shall be above 10mm.If in hot or wet environment place, the layer of
insulation should be thicker accordingly.
9.1.4
Installation highlights of insulation construction
➢
Gas pipe and liquid pipe shall be insulated separately, if the gas pipe and liquid pipe were insulated
together; it will decrease the performance of air conditioner.
Liquid pipe Insulation meterial Gas pipe
➢
The insulation material at the joint pipe shall be 5~10cm longer than the gap of the insulation material.
➢ The insulation material at the joint pipe shall be inserted into the gap of the insulation material.
➢ The insulation material at the joint pipe shall be banded to the gap pipe and liquid pipe tightly.
➢
The linking part should be use glue to paste together
➢
Be sure not bind the insulation material over-tight, it may extrude out the air in the material to cause bad
insulation and cause easy aging of the material.
9.2
Insulation of drainage pipe
9.2.1
Operational procedure of refrigerant pipe insulation
Select the suitable pipe
→ insulation (except joint section) → piping layout and connection→ drainage test→
insulate the joint parts
9.2.2
Purpose of drainage pipe insulation
The temperature of condensate drainage water is very low. If insulation is not enough, it shall form dew and
cause leakage to damage the house decoration.