Gree Ultra Heat GMV Multi VRF Heat Recovery Series Service Manual page 174

Ultra Heat GMV VRF Technical Service Manual_Heat Recovery Serial
3.Disassemble the four-way
valve.
4. Remove the four-way
valve.
5. Install a new four-way
valve.
6. Fix and wire the electric
box.
Use a screwdriver to unscrew accessories of
the four-way valve. Remove the accessories.
●Heat the connecting pipes of the four-way
valve by acetylene welding and then remove
the pipes.
●Record the direction of the valve and position
of the pipe joints.
Note: Avoid nearby parts from being burnt
during welding.
●Remove the four-way valve from the pipeline.
●Put the valve in a proper position.
●Weld the valve with the pipeline.
●Before welding, cover the valve with wet cloth
to avoid internal slide from being burnt and
prevent water from flowing in the pipeline.
●During welding, charge nitrogen into the pipes.
The pressure should be controlled within
0.5± 0.1 kgf/cm2 (relative pressure).
●Put the electric box back to original position
and screw it.
●Connect all lines.
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MAINTENANCE