R22 Units Refrigerant Charge; Characteristics Of The Refrigerant Fluid R22; Refrigerant Charge R22 - Liebert HIROSS Hisp SE Serie Manual De Usuario/ Instalacion

don' t stop the machine to allow the operation in
Freecooling mode in the proper conditions.
S The warning doesn' t cause the unit to stop.
S In case the safety heater thermostat intervenes, the
reset must be carried out on the thermostat, follow-
ing the same instructions as before.
5.3.4 --- Optional alarm board
Besides the components described for the standard
configuration, on the alarm card --- which can be sup-
plied as optional --- there are relay contacts to have the
following alarms separated:
1) Compressor high and low pressure
2) High temperature
3) Low temperature
4) Dirty filter alarm (if installed)
5) Fan fault
These alarms cause the unit to stop in the same ways as
described in the previous paragraph.
For a complete description of the alarms see the encl.
Microface manual.
5.3.5 --- Unit in stand--- by
The control of the units in stand---by is completely auto-
matic, thanks to the possibility of connecting the Micro-
face control. A unit in stand---by starts in case an alarm
stops the main unit; this occurs even if the main unit is
switched off or disappears from the system, due to a fault
on the control connecting bus.
The rotation of the units in stand---by occurs automati-
cally every 24 hours, so as to allow a homogeneous wear
of the system components.
If the system is connected to the Hiromatic interface, it is
possible to set a different rotation control.
If several units are simultaneously working with the same
set point, the temperature used for the control is the av-
erage of the detected ones; further, in the operation with
compressor, the proportional band is divided in as many
parts as twice the number of units belonging to the sys-
tem, so as to shut the total available refrigerating capac-
ity.
The operation in the Freecooling mode is homogeneous
and simultaneous on all units.
The Fig. L), shown as an example, describes the opera-
tion of a system consisting of 3 units.
Freecooling mode
Dead band
!P @ P band
1
3 2
Heating
Compressor cooling mode
Dead band
!P @ P band
1
3 2
Heating
1 = main unit
2 = unit in stand--- by
3 = unit in stand--- by
Fig. L --- A system consisting of 3 units, 2 of which in stand ---by ---
Microface control
English
!P @ P band
Set Cooling ° C
!P @ P band
1
2 3
Set Cooling ° C
6 --- R22 units refrigerant
charge
CAUTION: THESE OPERATIONS MUST BE PER-
FORMED BY AN EXPERT TECHNICIAN.
THE UNIT, AS SUPPLIED, IS PRECHARGED WITH
NITROGEN.
6.1 --- Characteristics of the refrigerant
fluid R22
At standard temperature and pressure it is a colourless
gas with low toxicity, non--- flammable, and it has an al-
lowed exposure limit value (AEL/TLV) corresponding
to 1000 ppm (average value measured on 8 hours per
day). In the event of leakage, air the room before use.

6.2 --- Refrigerant charge R22

WHEN REPAIRING THE REFRIGERATION CIR-
CUIT, PLEASE COLLECT ALL REFRIGERANT IN
A CONTAINER: DO NOT DISPOSE OF IT IN THE
ENVIRONMENT.
1) After connecting the refrigerating lines to the main
paths of the valves, placed on the evaporating and
motor condensing units, discharge the precharged
nitrogen by operating on the ¼ "SAE tap, with
needle valve, of the motor condensing unit.
2) Empty the circuit with the special (quality) vacuum
pump, applying a vacuum of 0.7 absolute mbar.
3) After 3 hours check not to have exceeded 1.3 abso-
lute mbar. If the vacuum is not kept there are leaks.
Repair the circuit and repeat the operations from
point 2.
4) Connect the charge cylinder to the liquid line of the
motor condensing and start charging the amount of
refrigerant R22 as shown in Tab. 10.
Tab. 10 --- Refrigerating charge R22 for a 5 m distance
between the evaporating and motor con-
densing units.
MODEL
Hisp SE+SC04
Hisp SE+SC05
Hisp SE+SC06
Hisp SE+SC08
Hisp SE+SC10
Hisp SE+SC13
Hisp SE+SC14
5) In case it is impossible to complete charging shift
the cylinder mode to compressor intake and com-
plete charging or however, after charging, operate
as follows:
6) Start up the unit as shown in par. 3.2.
7) Start the compressor manually.
8) Guarantee a constant condensation temperature
(preferably 50° C); if necessary, partially obstruct
the condenser exchange surface to obtain these
conditions.
9) Wait until the operating conditions of the whole re-
frigeration circuit are normal.
10)Make sure, while the system is in standard opera-
tion, that the superheating complies with following
values (Tab. 11: manometric temperatures are
shown).
10
Refrigerating charge R22 (kg)
2.3
2.3
2.5
4.3
4.4
4.4
4.4