Refrigeration Piping Installation - Emerson ZX User Manual

This work should Only be carried out by Suitably Qualified Electrical Technicians.
Please check the unit nameplate and run ample capacity three phase and single phase (including
neutral and earth wiring) to each unit. A suitably rated Isolating Switch ( this is also an Option
that could be selected ) should be fitted immediately adjacent to each unit .This is not only good
practice from a safety standpoint, but is usually a mandatory requirement for most electrical
supply authorities today.
All incoming phase lines are to be suitably fused at the Sub-Board to protect the installed wiring
and the unit.

9.0 Refrigeration Piping Installation

This work should Only be carried out by Suitably Qualified Refrigeration Technicians.
A good understanding of modern, Scroll Compressor Hermetic Systems is also essential when
carrying out this work-in particular, the importance of initial evacuation and charging procedures.
All interconnecting piping should be of refrigeration grade, clean, dehydrated and
remain capped at both ends until installation. Even during installation, if the system is
left for any reasonable period of time (say 2 hours), pipes should be re-capped to
prevent moisture and contaminant from entering the system.
It is advisable to insulate both the suction and liquid interconnecting piping between the ZX unit
and the evaporator. Usually the suction line is insulated, but the liquid line is not. However the
liquid line can pick up additional heat from the ambient and adversely affect the sub-cooling
desirable for the liquid refrigerant before it enters the expansion valve.
Pipe sizing should not only the sufficient size to ensure optimum performance and good oil return
but it also needs to take into account the full capacity range through which this particular unit will
need to operate.
Pipe runs should be kept as short as possible, using the minimum number of directional changes.
Use large radius bends and avoid trapping of oil and refrigerant. This is particularly important for
the suction line. The suction line should ideally slope gently toward the unit. Recommendation
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