Mitsubishi Electric ECOV-X37VA Manuel D'installation page 25

7. Refrigerant piping work
7-1. General information
• Improper design and installation of refrigerant piping may affect the function and life of cooling equipment, or occurrence of
problems. Design and install a water piping system according to the applicable regulations and the following instructions.
7-1-1. Removing the bypass pipe
The unit is charged with nitrogen gas prior to the shipment from the factory.
To prevent infiltration of water or contaminants, do not leave the pipe open until immediately before connecting the pipe.
To connect the bypass pipe, remove the gas in the pipe. Then weld the pipe after checking that the residual pressure is not
left.
1) Removing the bypass pipe
To remove the pipe that bypasses the suction pipe and
liquid pipe, first cut the bypass pipe at the section labeled
(A) to remove the nitrogen gas from the pipe, and then
debraze the pipe from sections labeled (a) and (b) in the
figure on the right.
Do not directly heat the brazed sections using a burner or
other heating device to remove the bypass pipe.
• When brazing the suction pipe or liquid pipe, use a slate board to protect the control devices and wires from the torch flame.
7-1-2. Notes on water and contaminants
Ester oil is used for this unit as refrigerant oil. Ester oil easily absorbs moisture and tends to cause deterioration of the refrig-
erant oil or formation of sludge (hydrate).
Use caution to prevent infiltration of contaminants such as water and dirt during piping work.
• Protect and maintain the pipes to prevent infiltration of contaminants such as water and dirt.
• Nitrogen purge is required to prevent formation of oxide scale while brazing the pipe.
1) Storage location
Store the pipes indoors. (Warehouse at site or owner's warehouse)
If the pipes are left outdoors, dust, dirt, or moisture may infiltrate and contaminate the pipes.
2) Sealing the pipe ends
Seal both ends of the pipes until just before brazing.
Keep elbow pipes and T-joints in plastic bags.
Do not reuse the existing pipes!
Brazed section (a)
Bypass pipe
Section A
25
Refrigerant service
valve (suction)
Strainer
Brazed section (b)
Cut here.
WT09614X03_GB