DC Inverter U-match Series Duct Type Unit
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to balance the pressure inside and outside of the connection pipe, so that air will
not come into the connection pipe when removing the hose. Note that the gas
and liquid valve can be opened fully only after the manifold valve assembly is
removed.
(8) Place back the caps of the liquid valve, gas valve and also the service port.
Notice:
For large-size units, there are maintenance ports for liquid valve
and gas valve. During evacuation, you may connect the two hoses of the branch
valve assembly to the maintenance ports to speed up the evacuation.
3.2.4.2 Leak Detection Methods
The following leak detection methods are deemed acceptable for systems
containing flammable refrigerants.
Electronic leak detectors shall be used to detect flammable refrigerants, but the
sensitivity may not be adequate, or may need re-calibration
(Detection equipment
shall be calibrated in a refrigerant-free area).
Ensure that the detector is not a potential source of ignition and is suitable for
the refrigerant used. Leak detection equipment shall be set at a percentage of the
LFL of the refrigerant and shall be calibrated to the refrigerant employed and the
appropriate percentage of gas (25% maximum) is confirmed.
Leak detection fluids are suitable for use with most refrigerants but the use of
detergents containing chlorine shall be avoided as the chlorine may react with the
refrigerant and corrode the copper pipe-work.
If a leak is suspected, all naked flames shall be removed / extinguished. If a
