6 | commissioning – GEA Bock HGX46 CO2 T User Manual
Page 29

 D
 GB
 F
 E
29
96259-12.2014-DGb
6.4 Evacuation
First evacuate the
system and then include the compressor in the evacuation process.
 Relieve the compressor pressure.
 Open the suction and pressure line shut-off valves.
 Turn on the oil sump heater.
 Evacuate the suction and discharge pressure sides using the vacuum pump.
 The vacuum has to be broken with nitrogen several times between the evacuation.
 At the end of the evacuation process, the vacuum should be < 1.5 mbar when the pump is switched off.
	 Repeat	this	process	as	often	as	is	required.
6| Commissioning
Make sure that the suction and pressure line shut-off valves are open.
6.5 Refrigerant charge
Filling	the	liquid	refrigerant:	It	is	recommended	that	the	system	first	be	filled	
at standstill with gas on the high-pressure side up to a system pressure of at 
least	5.2	bar	(if	it	is	filled	below	5.2	bar	with	liquid,	there	is	a	risk	of	dry	ice	
formation).	Further	filling	according	to	system.	
To eliminate the possibility of dry ice formation when the system is operating
(during	and	after	the	filling	process),	the	shut-off	point	of	the	low-pressure	
switch should be set to a value of at least 5.2 bar. 
A refrigerant supplement, which may become necessary after start-up, can
be topped up in vapour form on the suction side.
ATTENTION
Do not start the compressor if it is under vacuum. Do not apply 
any voltage - even for test purposes (must only be operated with 
 refrigerant).
Under vacuum, the spark-over and creepage current distances of the 
terminal board connection bolts shorten; this can result in winding and 
terminal board damage.
ATTENTION
Avoid overfilling the machine with refrigerant!
Do not charge liquid refrigerant into the suction-side on the
compressor.
Do not mix additives with the oil and refrigerant.
CAUTION
Wear personal protective clothing such as goggles and protective 
gloves!
WARNING
Never exceed the max. permissible pressures while charging. 
Precautions	must	be	taken	in	time.
INFO
Depending upon design of the CO
2
refrigerant filling bottle
(with/without tubing) CO
2
can be filled in liquid after weight or
gaseously.
Use only high-dried CO
2
quality!
