9-7. Charging additional refrigerant
9-7-1.When tubes are extended
• Observe the proper amount of refrigerant as stated in this service manual or the installation manual that came
with the indoor unit.
Charge additional refrigerant in liquid state.
●
Never charge additional refrigerant if refrigerant is leaking from the unit. Follow
instructions given in "10-6. In case refrigerant is leaking" and completely carry out
repairs. Only then should you recharge the refrigerant.
9-8. Retro-fitting existing systems
9-8-1 Use of existing units
•
Never use new refrigerant R407C for existing units which use R22. This will cause the air conditioner to
operate improperly and may result in a hazardous condition.
9-8-2 Use of existing tubing
• If replacing an older unit that used refrigerant R22 with a R407C unit,
do not use its existing tubing. Instead,
completely new tubing must be used.
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CAUTION
