Refrigerant Piping - Toshiba MMC-AP0158HP Series Installation Manual

6

Refrigerant piping

CAUTION
When the refrigerant pipe is long, provide support
brackets at intervals of 2.5 m to 3 m to clamp the
refrigerant pipe. Otherwise, abnormal sound may be
generated.
Use the fl are nut attached with the indoor unit or
R410A fl are nut.
■
Take out direction of
refrigerant pipe
• The refrigerant pipe connecting sections are located
as shown below. (Pipes can be taken out from one of
the three directions.)
• Make a pipe knockout hole, referring to the section
"Pipe knockout hole".
Upper
Back
Right
* When Drain Pump Kit (sold separately) is installed, a
refrigerant pipe can only be taken out from upper direction.
■
Permissible piping length and
height difference
They vary depending on the outdoor unit. For details,
refer to the Installation Manual attached to the outdoor
unit.
■
Pipe size
Pipe size (mm)
Model MMC-
Gas side Liquid side
AP015 to AP018 Ø12.7
AP024 to AP056 Ø15.9
27-EN
■
Connecting refrigerant piping
Flaring
1
Cut the pipe with a pipe cutter.
Remove burrs completely. (Remaining burrs may
cause gas leakage.)
2
Insert a fl are nut into the pipe, and fl are the
pipe.
Use the fl are nut provided with the unit or the
one used for the R410A refrigerant. The fl aring
dimensions for R410A are different from the ones
used for the conventional R22 refrigerant. A new
fl are tool manufactured for use with the R410A
refrigerant is recommended, but the conventional
tool can still be used if the projection margin of
the copper pipe is adjusted to be as shown in the
following table.
Projection margin in fl aring: B (Unit: mm)
Outer dia. of
R410A tool used
copper pipe
6.4, 9.5
0 to 0.5
12.7, 15.9
Flaring diameter size: A (Unit: mm)
Outer dia. of copper pipe
6.4
9.5
12.7
15.9
A
Ø6.4
Ø9.5
* In case of fl aring for R410A with the conventional
fl are tool, pull it out approx. 0.5 mm more than that
for R22 to adjust to the specifi ed fl are size. The
copper pipe gauge is useful for adjusting projection
margin size.
• The sealed gas was sealed at the atmospheric
pressure so when the fl are nut is removed, there
will no "whooshing" sound: This is normal and is not
indicative of trouble.
• Use two wrenches to connect the indoor unit pipe.
Work using double spanner
• Use the tightening torque levels as listed in the table
below.
Outer dia. of
Conventional
connecting pipe (mm)
tool used
6.4
1.0 to 1.5 9.5
12.7
15.9
• Tightening torque of fl are pipe connections.
Pressure of R410A is higher than that of R22.
(Approx. 1.6 times) Therefore, using a torque
wrench, tighten the fl are pipe connecting sections
which connect the indoor and outdoor units of the
specifi ed tightening torque.
Incorrect connections may cause not only a gas leak,
but also a trouble of the refrigeration cycle.
+0 CAUTION
A
–0.4
Tightening with an excessive torque may crack the nut
9.1
depending on installation conditions.
13.2
16.6
19.7
– 14 –
■
Evacuation
Perform vacuuming from the charge port of valve of
the outdoor unit by using a vacuum pump.
For details, follow to the Installation Manual attached to
the outdoor unit.
• Do not use the refrigerant sealed in the outdoor unit
for evacuation.
REQUIREMENT
For the tools such as charge hose, use those
manufactured exclusively for R410A.
Refrigerant amount to be added
For addition of the refrigerant, add refrigerant "R410A"
referring to the attached Installation Manual of outdoor
unit.
Use a scale to charge the refrigerant of specifi ed
amount.
REQUIREMENT
Tightening torque (N•m)
• Charging an excessive or too little amount of
refrigerant causes a trouble of the compressor.
14 to 18 (1.4 to 1.8 kgf•m)
Charge the refrigerant of specifi ed amount.
34 to 42 (3.4 to 4.2 kgf•m)
• A personnel who charged the refrigerant should
49 to 61 (4.9 to 6.1 kgf•m)
write down the pipe length and the added refrigerant
amount in the F-GAS label of the outdoor unit. It is
63 to 77 (6.3 to 7.7 kgf•m)
necessary to fi x the compressor and refrigeration
cycle malfunction.
Open the valve fully
Open the valve of the outdoor unit fully. A 4 mm-
hexagonal wrench is required for opening the valve.
For details, refer to the Installation Manual attached to
the outdoor unit.
Gas leak check
Check with a leak detector or soap water whether gas
leaks or not, from the pipe connecting section or cap
of the valve.
REQUIREMENT
Use a leak detector manufactured exclusively for HFC
refrigerant (R410A, R134a).
28-EN