Mitsubishi Electric PUZ-ZM60VHA2, Service Manual

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• Refer to the flowchart below to determine if the existing pipes can be used and if it is necessary to use a filter drier.
• If the diameter of the existing pipes is different from the specified diameter, refer to technical data materials to confirm if the
pipes can be used.
• If the existing air conditioner cannot operate, use a
refrigerant recovery device to collect the refrigerant.
• In case existing pipes were used for gas or oil
heat pump systems, be sure to clean the pipes.
Perform the airtight test, vacuum air purging,
additional refrigerant charging (if necessary),
and gas leak check.
Measure the existing pipe thickness and
check for damage.
The existing pipe thickness meets specifica -
tions and the pipes are not damaged.
Check if the existing air conditioner can operate.
After operating the cooling system for about 30
minutes, do a pump down work.
Disconnect the existing air conditioner from the
pipes.
Attach the new air conditioner
Test run
The existing pipes cannot be reused.
Use new pipes.
The existing pipe thickness does not meet
specifications or the pipes are damaged.
8
OCH771
2-3. PRECAUTIONS WHEN REUSING EXISTING R22/R410a REFRIGERANT PIPES
(1) Flowchart
[5] Service tools
Use the below service tools as exclusive tools for R32 refrigerant.
No. Tool name Specifications
1
Gauge manifold · Only for R32
· Use the existing fitting specifications. (UNF1/2)
· Use high-tension side pressure of 5.3MPa·G or over.
2
Charge hose · Only for R32
· Use pressure performance of 5.09MPa·G or over.
3
Electronic weighing scale
—
4
Gas leak detector
· Use the detector for R134a, R407C, R410a or R32.
5
Adaptor for reverse flow check
· Attach on vacuum pump.
6
Refrigerant charge base —
7
Refrigerant cylinder · Only for R32
· Cylinder with syphon
8
Refrigerant recovery equipment —