Hitachi UTOPIA Manual De Instrucciones página 30

REFRIGERANT PIPING & REFRIGERANT CHARGE
8.4 REFRIGERANT CHARGE
!
C A U T I O N
• Do not charge OXYGEN, ACETYLENE, or other flammable and
poisonous gases into the refrigerant because an explosion can occur.
It is recommended that oxygen free nitrogen be charged for these
types of tests cycle when performing a leakage test or an airtight test.
These types of gases are extremely dangerous.
• Insulate the unions and flare-nuts at the piping connection part
completely.
• Insulate the liquid piping completely to avoid a decrease of
performance; if not, it will cause sweating on the surface of the pipe.
8.5 REFRIGERANT CHARGING QUANTITY
In case of the actual piping length is more than the specified length, the additional refrigerant quantity should be charged according
to the table below:
Outdoor unit refrigerant charge
(kg)
1.7
1 Determine an additional refrigerant quantity according to the
following procedure, and charge it into the system.
2 Record the additional refrigerant quantity to facilitate service
activities thereafter.
8.6 CAUTION OF THE PRESSURE BY CHECK JOINT
When the pressure is measured, use the check joint of gas stop
valve, and use the check joint of liquid piping in the figure below.
10 PMML0548 rev.0 - 04/2020 - A10648790A
Chargeless length (m)
20
Stop valve (liquid)
Stop valve (gas)
• Charge refrigerant correctly. Overcharging or insufficient charging
could cause a compressor failure.
• Check for refrigerant leakage in detail. If a large refrigerant leakage
occurred, it would cause difficulty with breathing or harmful gases
would occur if a fire were being used in the room.
• If the flare nut is tightened too hard, the flare nut may crack after a
long time and cause refrigerant leakage.
Additional refrigerant charge (P)
(g/m)
30
!
C A U T I O N
• When charging refrigerant accurately measure refrigerant to be
charged.
• Overcharging or undercharging of refrigerant can cause compressor
trouble.
• In case of actual piping length less than 5 m, consult your distributor.
• Charge refrigerant correctly. Overcharging or insufficient charging
could cause a compressor failure.
At that time, connect the pressure gauge according to the
following table because of high pressure side and low pressure
side changes by operation mode.
Check joint for gas stop valve
Check joint for liquid stop valve
?
N O T E
Be careful that refrigerant and oil do not splash to the electrical parts at
removing the charge hoses.
Max additional charge (kg)
0.9
Cooling Heating
operation operation
Low pressure High pressure
Exclusive for vacuum pump and
refrigerant charge