74
EN/06.2016/i09 © STULZ S.p.A. – all rights reserved
WSA ExplOrEr OriginAl inStructiOnS
Description
Six month
One year
Five year
Check for fugue
Tightness of the refrigerant circuit
Check the high pressure safety switch
Check the high pressure and low pressure switch
Sobstitute the pressure relief valve (Directive 97/23/CE)
Air circuit
Clean the W-modules
Check the mounting, operation and balancing of fans
Water circuit
Clean the water filter
Check the level of the fluid to be cooled
Check the presence of air
Check and repair any leaks
Check and repair the fault insulation of pipes
Check the connections
Check the efficency of the differential pressure switch
Check the efficency of the flow swich (options)
Check the cleanliness of the evaporator water side
Electric circuit
Check for abnormal consumption
Check the tightness of all terminals
Check the cleanliness and integrity of the contatctors
Check the connections of the pressure switches
unit in general
Check the absence of abnormal vibration
Check the absence of abnormal noise
8.3 refrigerant circuit
8.3.1 refrigerant charge
To be checked: sight glass, LP switch
An insufficient charge causes the formation of bubbles in the sight glass (at full load) or in
extreme cases the triggering of the LP switch. An operation with an insufficient refrigerant quan-
tity over a longer period leads to a reduction of cooling capacity and to high super-heating tem-
peratures, which have a disadvantageous effect on the compressor lifetime.
If a leak is detected:
• evacuate all the refrigerant gas and dispose it according to the national regulation
• repair the leak
• do a pressure test by nitrogen
• extract the nitrogen by the vacuum pump (not by the compressor!) to approximately 0 barg
• fill with refrigerant gas according to name plate of the chiller for type and weight
