Mitsubishi Electric PUZ-SWM AA Series Installation Manual page 17

4. Installing the refrigerant piping
A
D
E
F
G
A Stop valve <Liquid side>
B Stop valve <Gas side>
C Service port
D Open/Close section
Fig. 4-4
(1)
B
A
H
I
J
F
E
Fig. 4-5
A Valve body I Double spanner section
B Unit side (Do not apply a spanner other than to this section.
C Handle Doing so would cause coolant leaks.)
J Seal section
D Cap
E Local pipe side (Seal the end of the heat insulation material at the
F Pipe cover pipe connection section with whatever seal mate-
G Service port rial you have on hand so that water does not infil-
H Valve stem trate the heat insulation material.)
B
C
Fig. 4-7
B
C
D
E
F
G
E Local pipe
F Sealed, same way for gas side
G Pipe cover
(2)
B
G
A
D D
H
I
J
F
E
Fig. 4-6
A
* The figure to the left is an example only.
The stop valve shape, service port position,
etc., may vary according to the model.
* Turn section A only.
(Do not further tighten sections A and B
D
together.)
C Charge hose
D Service port
4.4. Refrigerant pipe airtight testing method (Fig. 4-4)
(1) Connect the testing tools.
• Make sure the stop valves A B are closed and do not open them.
• Add pressure to the refrigerant lines through the service port C of the Gas stop
valve B .
(2) Do not add pressure to the specified pressure all at once; add pressure little by
little.
1 Pressurize to 0.5 MPa (5 kgf/cm
pressure does not decrease.
2 Pressurize to 1.5 MPa (15 kgf/cm
pressure does not decrease.
3 Pressurize to 4.15 MPa (41.5 kgf/cm
perature and refrigerant pressure.
(3) If the specified 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) Liquid side (Fig. 4-5)
1 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.
(Approximately 4 revolutions)
2 Make sure that the stop valve is open completely, push in the handle and rotate
the cap back to its original position.
(2) Gas side (Fig. 4-6)
1 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.
(Approximately 9 revolutions)
2 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
• 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
• 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.)
CAUTION:
Precautions when using the charge valve (Fig. 4-7)
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 B in the desired direction, turn
section A only and tighten it.
Do not further tighten sections A and B together after
tightening section A.
G), wait five minutes, and make sure the
2
G), wait five minutes, and make sure the
2
G) and measure the surrounding tem-
2
16
en