Technical Description; Use Of Manifold - Refco M2-3-Deluxe-DS-R744 Mode D'emploi

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Technical description

The 2-way manifold is a high precision instrument. Both gauges, high and low pressure
can be readjusted to the zero point. The manifold gauges are marked with temperature
and pressure scales.
The scales of the suction and pressure gauges only contain temperature values up to the
critical point of R744 (CO2). This point is reached at the critical pressure 73.75 bar (a) with
the critical temperature 30.98°C. At higher pressures, the refrigerant is in the transcritical
state. Therefore, no temperature can be assigned due to lack of wet steam area.
Changeable nedle type valves ensure perfect sealing. Glycerine-oil filled gauges are
equipped with a safety pressure relief in case of a pressure build up inside the gauge
due to a defect.

Use of manifold

Preparing
Before use ensure that the temperature scales on the manifold gauges match the refrige-
rants used in the system. Adjust the gauge with the zero adjusting screw to zero. Position
of the hand may vary and might not point to zero depending on the atmospheric pressure.
Readjusting the gauge might therefore be necessary before each use of the manifold. The
zero adjusting screw is positioned either at the top or through the front lens depending
on the type of manifold.
Connecting the manifold to a system
• Connect hose from blue valve to system suction pressure side
• Connect the hose from the red valve to the high pressure system
• Connect the hose from the middle connection to the vacuum pump
• Close Both valves (6+7)
Evacuation of a system
• Switch on vacuum pump
• Open both valves (6+7)
• Check negative pressure on low pressure gauge
• When final vacuum reached, close both valves (6+7)
Please note: The evacuation time may vary depending on the size of the sys-
tem. A minimal time span of 20 minutes must be reserved to evacuate a small
to middle sized system.
Filling of a system after evacuation
• Disconnect the hose from the vacuum pump and screw it to the refrigerant cylinder
or cylinder.
• Filling process according to the instructions of the plant or compressor manufacturer
m If liquid is filled at less than 5.2 bar, there is a risk of dry ice formation!