Refrigerant Loading - Trane CXAO Installation Operation & Maintenance

5.6

Refrigerant loading

WARNING!
The units are designed to work with R134a refrigerant.
DO NOT USE different refrigerants from R134a. The
addition or removal of refrigerant gas must be done in
accordance with the laws and regulations in force.
When you add or remove the refrigerant from the
system, ensure the proper fl ow of water through the
evaporator for the entire period of charge / discharge.
The interruption of the fl ow of water during this
procedure would result in the freezing of the evaporator
resulting in rupture of its internal pipes. Damage due to
freezing will void the warranty.
The removal of refrigerant and charging the battery
should be made by qualifi ed technicians in the use of
material appropriate for the unit. Improper maintenance
can lead to uncontrolled pressure loss and fl uid. Do
not disperse the refrigerant and the lubricating oil in
the environment. Always wear a special protective
equipment.
Units are shipped with the total refrigerant charge, but in
some cases the refrigerant may need to be refi lled in the
fi eld.
Always check the causes that have led to a loss of
refrigerant. If necessary, repair the system and then
proceed to its charging.
RF-SVX003A-GB
The charging of the unit can be made in any load
condition stable (preferably between 70 and 100%) and
in every condition of temperature (preferably higher
than 20 °C). The unit should be maintained turned on
for at least 5 minutes to allow the stabilization of the
steps of the fans, and then the pressure of condensation.
The units have about 15% of the condensing coils
dedicated to the subcooled liquid refrigerant. the value
of subcooling is equal to about 5-6 °C (10-15 °C for units
economized). Once the section of subcooling has been
completely fi lled, a further quantity of refrigerant is not
increases the effi ciency of the system. However a small
amount of additional refrigerant (1 or 2 kg) makes the
system less sensitive.
Note: By varying the load and the number of active
fans, subcooling varied and requires some time to
restabilize. However it should never drop below 3 °C in
all conditions. Furthermore, the value of subcooling may
change slightly with changes in temperature of the water
and the superheat of suction.
One of the following two scenarios may occur in a unit
discharge of refrigerant:
1. If the unit is slightly discharge of refrigerant through
the sight glass you can see the passage of bubbles.
The circuit as described in the charging process.
2. If the unit has a reduction of refrigerant charge, the
corresponding circuit could have low pressure alarm.
Prime the circuit as described in the corresponding
charge.
Refrigerant loading
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