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Siemens Modulating refrigerant valves, PN 63 CE2N4717en

Smart Infrastructure 2019-11-25

Engineering notes

Depending on the application, it may be necessary to observe additional Installation

Instructions and fit appropriate safety devices (e.g. pressurestats, full motor protection,

etc.).

In order not to damage the seal inside the valve insert, the plant must be vented on the

low-pressure side after the pressure test has been made (valve port AB), or the valve

must be fully open during the pressure test and during venting (power supply connect-

ed and positioning signal at maximum or forced opening by G → ZC).

To prevent the formation of flash gas on expansion applications, the velocity of the

refrigerant in the fluid pipe must not exceed 1 m/s. To assure this, the diameter of the

fluid pipe must under certain circumstances be greater than the nominal size of the

valve.

1 = evaporator

2 = compressor

3 = condenser

4 = expansion valves

a) The differential pressure over reduction must be less than half the differential

pressure Δp

b) The inlet path between diameter reduction and expansion valve inlet

 Must straight for at least 600 mm

 May not contain any valves

A filter / dryer must be mounted upstream of the expansion valve.

The valve is not explosion-proof.

Warning

Expansion application

Engineering notes