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IOM_CCHIBA-CSTIBA_301_207925_170706_EN
CCHIBA/CSTIBA
SPLIT HORIZONTAL INVERTER UNITS
PACKAGED AIR-AIR
REFRIGERANT CHARGE
Should it be necessary to add or recover refrigerant, do it always in LIQUID phase, never in gas or vapour phase
since this would cause wrong mixing conditions.
Due to its high pressure and quick evaporation, refrigerant R410A cannot be kept in liquid phase inside charge
cylinder because bubbles would form, making reading difficult. Use always a scale to charge the unit with refrigerant.
Repair immediately any refrigerant leak.
Never overcharge the system.
Never use compressor as a vacuum pump.
If symptoms of refrigerant loss appear during
operation, it’s necessary to carry out a leak test. Leak detectors usually
employed with CFC and HCFC cannot be used with R410a, due to chlorine in its composition. A leak detector for
R134A can be used but the sensitibity will be lower (when sensitibity is 1 for R134A, it falls to 0,6 for R410A).
To find small leaks, you will need a detector for HCF. Sensitibity for R410A is approx. 23 grams per year.
If a gas leak is found, it will be necessary to remove and completely recover the refrigerant charge. Pressurize the
system with dry nitrogen. If no leakage is detected, then do the vacuum and charge again with refrigerant.
Never use oxygen to carry out leak tests. Oxygen reacts violently when in contact
with oil and could cause an explosion resulting in damage, personal injuries or even
death.
If it’s necessary to make welding operations, you must fill the circuit with dry
nitrogen. Combustion of R410A refrigerant generates toxic gases.
