Mitsubishi Electric PUHZ-SW HA Series Installation Manual page 7

4. Installing the refrigerant piping
Stop valve <Liquid side>
Stop valve <Gas side>
Service port
Open/Close section
Fig. 4-5
(1) (2)
Fig. 4-6 Fig. 4-7
Valve Double spanner section
Unit side (Do not apply a spanner other than to this section.
Handle Doing so would cause coolant leaks.)
Cap Seal section
Local pipe side (Seal the end of the heat insulation material at
Pipe cover the pipe connection section with whatever seal
Service port material you have on hand so that water does not
Wrench hole in ltrate the heat insulation material.)
Fig. 4-9
Local pipe
Sealed, same way for gas side
Pipe cover
(3)
Fig. 4-8
* The  gure to the left is an example only.
The stop valve shape, service port position,
etc., may vary according to the model.
* Turn section only.
(Do not further tighten sections and
together.)
Charge hose
Service port
4.4. Refrigerant pipe airtight testing method (Fig. 4-5)
(1) Connect the testing tools.
• Make sure the stop valves
• Add pressure to the refrigerant lines through the service port
stop valve .
(2) Do not add pressure to the speci ed pressure all at once; add pressure little by
little.
Pressurize to 0.5 MPa (5 kgf/cm
pressure does not decrease.
Pressurize to 1.5 MPa (15 kgf/cm
pressure does not decrease.
Pressurize to 4.15 MPa (41.5 kgf/cm
perature and refrigerant pressure.
(3) If the speci ed pressure holds for about one day and does not decrease, the
pipes have passed the test and there are no leaks.
• If the surrounding temperature changes by 1 °C, the pressure will change by
about 0.01 MPa (0.1 kgf/cm G). Make the necessary corrections.
2
(4) If the pressure decreases in steps (2) or (3), there is a gas leak. Look for the
source of the gas leak.
4.5. Stop valve opening method
The stop valve opening method varies according to the outdoor unit model. Use the
appropriate method to open the stop valves.
(1) Gas side of SW75 (Fig. 4-6)
Remove the cap and turn the valve rod counter clock wise as far as it will go with
the use of a 5 mm hexagonal wrench. Stop turning when it hits the stopper.
(ø 15.88: Approximately 13 revolutions.)
Make sure that the stop valve is open completely and rotate the cap back to its
original position.
(2) Gas side of SW100-200 (Fig. 4-7)
Remove the cap, pull the handle toward you and rotate 1/4 turn in a counter-
clockwise direction to open.
Make sure that the stop valve is open completely, push in the handle and rotate
the cap back to its original position.
(3) Liquid side of SW75-200 and Gas/Liquid side of SW40-75 (Fig. 4-8)
Remove the cap and turn the valve rod counterclockwise as far as it will go with
the use of a 4 mm hexagonal wrench. Stop turning when it hits the stopper.
(ø9.52: Approximately 10 revolutions)
Make sure that the stop valve is open completely, push in the handle and rotate
the cap back to its original position.
Refrigerant pipes are protectively wrapped for SW75-200
• The pipes can be protectively wrapped up to a diameter of ø90 before or after
connecting the pipes. Cut out the knockout in the pipe cover following the groove
and wrap the pipes.
Pipe inlet gap for SW75-200
• Use putty or sealant to seal the pipe inlet around the pipes so that no gaps re-
main. (If the gaps are not closed, noise may be emitted or water and dust will
enter the unit and breakdown may result.)
Precautions when using the charge valve (Fig. 4-9)
Do not tighten the service port too much when installing it, otherwise, the valve core
could be deformed and become loose, causing a gas leak.
After positioning section in the desired direction, turn section
Do not further tighten sections and
Warning:
When installing the unit, securely connect the refrigerant pipes before start-
ing the compressor.
are closed and do not open them.
of the liquid
G), wait five minutes, and make sure the
2
G), wait  ve minutes, and make sure the
2
G) and measure the surrounding tem-
2
only and tighten it.
together after tightening section .