GREE                                                                        GMV5E DC INVERTER VRF UNITS SERVICE MANUAL 
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6.3 Insulation System 
6.3.1 Insulation for the Refrigerant Pipe System 
6.3.1.1 Insulation Materials 
Use closed-cell foam insulation materials with flame retardant grade of B1.   
The heat conductivity is not greater than 0.035 w/(m·k) when the average temperature is 0°C. 
6.3.1.2 Thickness of the Insulation Layer 
Use sunblock, anti-weathering, and non-cracking insulation materials for outdoor pipes. 
6.3.1.3 Procedure of Insulation 
a) Select insulation materials based on design requirements. 
b) Wear the insulation sleeve before connecting refrigerant pipes. Users cannot cut the insulation 
material apart and then wrap up with ties after connecting the pipes by welding. 
c) Specifications of the insulation sleeve must match with that of the refrigerant pipes. 
d) Reserve a  distance  of  about 200  mm  near the  welding  point  to  protect the insulation  sleeve 
during welding. After performing the  air-tightness test, perform insulation  to the welding point 
separately to ensure continuity of the insulation sleeve.   
e) The insulation layer cannot crack during construction. Bond the insulation material  joints with 
special glue and then wrap them with electrical adhesive tape. The width of the adhesive tape 
must be 50 mm or more to ensure secure connection. 
f) Use glue to bond the insulation material at the water outlet to the unit to prevent dewing. 
g) Wrap joints of indoor/outdoor units with insulation materials. There must be no gap between the 
joint and the wall of the indoor/outdoor unit, as shown in the following figure. 
 
6.3.2 Insulation for the Condensate Water Pipe System 
(1) Insulation Materials 
Use closed-cell foam insulation materials with retardant grade of B1.   
The heat conductivity is not greater than 0.035 w/(m·k) when the average temperature is 0
°C
. 
(2) Thickness of the Insulation Layer 
Thickness of the insulation layer for the condensate water pipe must be greater than 10 mm. 
(3) Bond the insulation material joints with special glue and then wrap them with plastic adhesive. 
The width of the adhesive must be greater than 5 cm to prevent dewing. 
(4) Insulation is not required for the outdoor part of condensate water pipes.