McQuay MDS030AR Applications Manual page 88

Design & installation Guide For McQuay MDS Multi System
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Gas pipe
Liquid pipe
Control
cable
Heat
Surface
preservation
binding
The connecting port should
be heat-insulated completely
Connecting
port is not
heat-insulated
The thickness of insulation materials depends on the pipe size.
Pipe size
6.4mm~25.4mm
28.6mm~38.1mm
In case the environment is hot and damp, increase the recommended thickness (1 inch for
the main pipe, and half inch for the refnet joint) in the table above.
For the cooling only unit, if it is predicted that the system might run in the ambient
temperature of less than 10 degrees Celsius, the liquid pipe should also be insulated.
4.3.10 Ball Valve Operation
Ball valve operation procedures
Make sure the pipes are connected and the valves are
operated correctly. Please install and operate the valves
as follows:
Gas side ball valve operation
1) Remove the connection pipe with flange: Re-
move the connection pipe with flange from the
gas side ball valve and braze it to the outside of
the unit.
2) Stick the sealing material: When removing the
connection pipe and flange, remove the sealing
material on the ball valve label and stick it on the
flange of the ball valve to prevent dusts into the
ball valve.
3) Replace the hollow gasket: Before delivery, seal the refrigerant circulation loop with
a round solid sealing plate to avoid gas leakage between flanges. In such status,
the system cannot run. So, please replace with the hollow gasket on the ball valve.
Before installing the hollow gasket, clean the flange surface and the sealing plate.
4) Fix the connection pipe welded with gas pipe, hollow gasket and gas ball valve with
screws.
Connection of the liquid side stop valve: Expand the flare fitting of the copper pipe.
Then, connect it with the threaded stop valve.
After pumping vacuum and fill refrigerant, make sure the valve is fully open. If the
system runs when the valve is closed, the unit pressure will be abnormal, damaging
the compressor and four-way valve.
Calculate the refrigerant amount to be added with the formula (refer to Section 9.3),
and fill the amount through the access opening when the pipe connection work is
complete.
After the work is finished, firmly fix the access opening and cap to avoid gas leakage.
Only the gas pip e is heat- The gas and liquid pipe are heat-
insulated
insulated
Gas pipe
Heat
Liquid pipe
preservation
Control
cable
Gas
pipe
Heat
Surface
Surface binding
preservation binding
Moisture preservation support
Heat
preservation
Liquid
pipe
Control cable
Copper pipe
Heat preservation
Metal support
Camber pad
Thickness of the insulation material
10mm or more
15mm or more
S
O