Mitsubishi Electric PUHZ-FRP71VHA2 Installation Manual page 11

8. Special functions
8.3. Refrigerant collecting (pump down) (Fig. 8-3)
The refrigerant collecting function is available by performing the following procedure.
1 Close the 2 liquid stop valves and the cylinder/hydro unit side gas valve.
Only the indoor unit side gas valve remains open.
2 Connect the 2 gas stop valve service ports with a hose.
3 Turn on the main power and wait for 3-4 minutes.
4 Press the SWP button on the outdoor controller board, then the refrigerant collecting operation starts.
5 After confirming the low pressure is lowered to 0 MPa (gauge), close the indoor unit side gas valve.
The refrigerant collecting operation stops automatically in 5 minutes.
6 Turn off the main power.
Stop valve
Hose
Service port
Stop valve
Service port
Cylinder/
Indoor
Hydrobox
LEV-B
UNIT
UNIT
Stop valve
Service port
Stop valve
Service port
Warning:
Do not disconnect extension pipes during the refrigerant collecting operation is running.
If you open the stop valves to the air during the compressor is running, the pressure could be abnormal high level and this may cause a rupture
of the compressor or other hazardous situation.
* Use a refrigerant recovery machinery if the refrigerant collecting is not completed in case of long pipe length or too much refrigerant contained.
4-way valve
SV3 SV1
Charge
plug
Accumulator
Muffler
TH33
LEV-C
TH4
LEV-A
Compressor
* SV1/SV2/SV3 are closed when the power is not supplied.
Fig. 8-3
TH7
TH6
SV2
Charge plug TH3
High pressure
sensor(63HS)
High pressure
switch (63H)
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