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2WAY SYSTEM
Outdoor Unit Repair Procedures
3
4. Recovering Refrigerant
The following equipment and tools are required:
Jumper wire with clips, adjustable wrench, set of manifold gauge valves specially designed for refrigerant R410A
only, vacuum pump, refrigerant recovery unit, pre-purged refrigerant cylinder for recovery, flathead screwdriver, and
outdoor unit maintenance remote controller.
4-1. Refrigerant Recovery Procedures (from outdoor unit)
(1) Turn off the power of the outdoor unit beforehand (at power mains).
(2) Fully close each service valve on the liquid tube, gas tubes, and the balance tube of the outdoor unit.
(3) Connect the outdoor unit’s high-pressure and low-pressure outlet ports with the Hi and Lo sides of the mani-
fold gauge valves using hoses. (Fig. 3)
The remaining refrigerant in the faulty outdoor unit may create internal pressure.
Before connecting hoses, be sure to confirm that each of the manifold gauge
valves is tightly closed. Note that the connection ports employ Schrader-type
push-to-release valves.
CAUTION
(4) Connect the manifold gauge valves, refrigerant recovery unit, and recovery cylinder using hoses. To avoid the
entry of air into the refrigerant tubing, carry out this connection work carefully. (Fig. 3)
For detailed procedures such as connecting the refrigerant recovery unit with the
recovery cylinder and methods used for recovery, follow the specific instructions
that came with the refrigerant recovery unit.
CAUTION
(5) Locate the AP (Air Purge) pins on the control PCB in the faulty outdoor unit and short them using the clips of
the jumper wire. Then restore electrical power to the outdoor unit.
By short-circuiting the AP pins, each solenoid valve in the outdoor unit is forcibly
opened as soon as power comes on, which releases all remaining refrigerant into
the recovery cylinder. Since neglecting this procedure may leave some refrigerant
in the system, it is important that you carry out this step.
CAUTION
(6) Carry out refrigerant recovery.
To determine the completion of refrigerant recovery, follow the instructions that
came with the refrigerant recovery unit.
CAUTION
High-pressure outlet port
(for ø7.94mm-dia connector)
Liquid tube service port
(for ø7.94mm-dia connector)
Gas tube service port
(for ø7.94mm-dia connector)
Type 8HP / 10HP / 12HP
Refrigerant recovery cylinder
Refrigerant
recovery unit
Manifold
gauge
Lo Hi
Low-pressure outlet port
(for ø7.94mm-dia connector)
Fig. 3-a
SM830204-05_2WAY SYS_new.indb 8 15/01/05 15:31:29
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