59
GRFP
Fig. 8-5
Fig. 8-6
8-3. Charging Additional Refrigerant
●
Charging additional refrigerant (calculated from the
narrow tube length as shown in P. 12, Amount of
additional refrigerant charge) using the narrow tube
service valve. (Fig. 8-5)
●
Use a balance to measure the refrigerant accurately.
●
If the additional refrigerant charge amount cannot
be charged at once, charge the remaining refriger-
ant in liquid form by using the wide tube service
valve with the system in Cooling mode at the time
of test run. (Fig. 8-6)
* If an additional refrigerant charge has been per-
formed, list the refrigerant tubing length and
amount of additional refrigerant charge on the
product label (inside the panel).
8-4. Finishing the Job
(1) With a hex wrench, turn the narrow tube service
valve stem counter-clockwise to fully open the
valve.
(2) Turn the wide tube service valve stem counter-
clockwise to fully open the valve.
(3) Loosen the charge hose connected to the wide
tube service port (5/16 in.) slightly to release the
pressure, then remove the hose.
(4) Replace the 5/16 in. flare nut and its bonnet on the
wide tube service port and fasten the flare nut
securely with an adjustable wrench or box wrench.
This process is very important to prevent gas from
leaking from the system.
(5) Replace the valve caps at both wide and narrow
service valves and fasten them securely.
CAUTION
To avoid gas from leaking
when removing the charge
hose, make sure the stem of
the wide tube is turned all
the way out (“BACK SEAT”
position.
Valve
Liquid
Manifold valve
Pressure
gauge
Lo
Hi
Outdoor unit
Narrow
tube
Wide
tube
Close
Close
Close
R410A
Outdoor unit
Narrow
tube
Wide
tube
Open
Open
Open
04-393 DC INV Tech p 45-63 12/13/04 11:34 AM Page 59
