49
(5) Recharging
●
Be sure to charge the specified amount of
refrigerant in liquid state
using the service port
of the wide tube service valve. The proper
amount is listed on the unit's nameplate.
When the entire amount cannot be charged all at
once, charge gradually while operating the unit
in Cooling Operation.
●
When charging with a refrigerant cylinder, use
an electronic scale for charging refrigerant. In
this case, if the volume of refrigerant in the cylin-
der becomes less than 20% of the fully-charged
amount, the composition of the refrigerant starts
to change. Thus,
do not use the refrigerant if
the amount in the charging cylinder is less
than 20%.
Also, charge the minimum necessary amount to
the charging cylinder before using it to charge
the air conditioning unit.
Example:
In case of charging refrigerant to a unit requiring
0.76Kg using a capacity of a 10Kg cylinder, the
minimum necessary amount for the cylinder is:
0.76 + 10
×
0.20 = 2.76Kg
For the remaining refrigerant, refer to the
instructions of the refrigerant manufacturer.
●
If using a charging cylinder, transfer the speci-
fied amount of liquid refrigerant from the refriger-
ant cylinder to the charging cylinder.
Prepare an evacuated charging cylinder before-
hand.
Do not use the refrigerant if the amount in
the charging cylinder is less than 20%.
CAUTION
Never charge a large amount
of liquid refrigerant at once to
the unit. This may cause dam-
age to the compressor.
CAUTION
●
To prevent the composition
of R410A from changing,
never bleed the refrigerant
gas into the atmosphere
while transferring the refrig-
erant. (Fig. 3)
Valve
Single valve
Charge liquid refrigerant with
cylinder in up-side-down position.
Liquid
Fig. 1
Valve
Single valve (with siphon tube)
Charge with cylinder in normal position.
Liquid
Fig. 2
Charging
cylinder
Open
Refrigerant
cylinder
Liquid
NO!
Fig. 3
Configuration and characteristics of cylinders
