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Leak Detection; Vacuum Procedure; Electrical Connections - Danfoss Performer SZ R407C Instruktion

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Instructions
holding charge.
Ensure that no material enters into the system
while cutting the tubing. Moreover, never drill
holes in the pipe work after installation.
Should additional components need to be
connected on to the compressor sight glass or
oil equalization ports, it is recommended that
such an operation be carried out prior to final
assembly, to allow for compressor inclination
and movement.
Avoid flare-type connections and exercise great
care while brazing (use only state-of-the-art
practices); apply a nitrogen gas flow to prevent
oxidation inside the tubing, especially when HFC
refrigerants are being used. All brazing material
is to contain a minimum of 5% silver.
When brazing, protect the terminal box and
painted surfaces of the compressor from torch
heat damage.
For compressors equipped with Rotolock, re-
move the Teflon gaskets when brazing Rotolock
connectors with the solder sleeve and be aware
that original suction and discharge gaskets must
be replaced.
When installing Rotolock fittings, always use
two wrenches when tightening any fittings to
ensure that the torque is effectively cancelled on
the adjacent tubing and fittings. Do not exceed
the maximum tightening torque for Rotolock
connections to the compressor. (1'' Rotolock
80Nm - 1''1/4 Rotolock 90Nm 1''3/4 Rotolock
110Nm - 2''1/4 Rotolock 130Nm).
Be sure to connect the required safety and
control devices onto compressor shutoff valves
or fittings.
In case of oil return through the Schrader fit-
ting on the compressor shell, make sure the in-
ternal valve is removed.
5 – Leak detection
Never use oxygen or dry air in order to avoid
the risk of fire or explosion.
Perform a leak detection test on the complete
system by means of: a dry nitrogen pressure
test, a mixture of nitrogen and the refrigerant to
be used in the system, a helium leak test and/or
a deep vacuum test.
The test should be long enough in duration
to ensure the absence of any slow leaks in the
system.
Use tools specifically designed for detecting
leaks.
The low side test pressure must not exceed 25
bars for SM/SZ compressors, 20 bars for SY/SZ
240 - 300 - 380, 30 bars for the SH 180 - 240 - 300
- 380 compressors and 33.3 bars for SH 090 - 105
- 120 - 140 - 161 compressors.
For high side test pressure recommendations,
please refer to the Application Guidelines.
Whenever the compressor is equipped with
suction and discharge shut-off valves, these
valves are to remain in the closed position while
performing the leak test (compressor leak test

already performed in the factory).
Should a leak be discovered, proceed with re-
pair steps and repeat the leak detection.
When a deep vacuum leak detection test is se-
lected, observe the following:
1) The level to reach is 500 μm Hg. Wait 30
min.
2) If pressure increases rapidly, the system is
not airtight. Locate and repair leaks. Restart the
vacuum procedure, followed by steps 1, 2, etc.
3) If pressure increases slowly, the system
contains moisture inside. Break the vacuum with
nitrogen gas and restart the vacuum procedure,
followed by steps 1, 2, etc.
4) Connect the compressor to the system by
opening the valves.
5) Repeat the vacuum procedure, followed by
steps 1, 2, etc.
6) Break the vacuum with nitrogen gas.
7) Repeat the vacuum procedure, steps 1,2; a
vacuum of 500 μm Hg (0.67 mbar) should be rea-
ched and maintained for 4 hours. This pressure
is to be measured in the refrigeration system,
not at the vacuum pump gauge.
Do not use a megohmeter or apply power to
the compressor while it is under vacuum, as this
may cause motor winding damage (motor burn-
out).
Do not use colored leak detection fluids. Do
not use chlorofluorocarbon in leak testing sys-
tems designed for HFC fluids.

6 - Vacuum procedure

Whenever possible (if shut-off valves are pre-
sent), the compressor must be isolated from the
system. It is essential to connect the vacuum
pump to both the LP & HP sides, in order to avoid
dead-ending system parts.
Recommended procedure:
1) Once leak detection has been completed,
pull down the system under a vacuum of 500 μm
Hg (0.67 mbar).
2) When the vacuum level of 500 μm Hg has
been reached, the system must be isolated from
the pump.
3) A vacuum of 500 μm Hg (0.67 mbar) has
to be reached and maintained for 4 hours. This
pressure is to be measured in the refrigeration
system, not at the vacuum pump gauge.If pres-
sure increases, restart the leak-detection proce-
dure (refer to the "Leak detection" section of
this manual if necessary).
Vacuum pump:
A two-stage vacuum pump with gas ballast
(0.04-mbar standing vacuum) shall be used;
its capacity is to be consistent with system vo-
lume.Never use the compressor as a vacuum
pump. It is recommended to use large-diameter
connection lines and to connect these lines to
the shutoff valves, rather than to the Schrader
connection. This recommendation allows avoi-
ding excessive pressure losses.
8510197P03
© Danfoss Commercial Compressors April-2007
Moisture level:
At the time of commissioning, system moisture
content may be as high as 100 ppm. During ope-
ration, the liquid line filter dryer must reduce
this level to < 20 ppm.
Additional notes:
To improve moisture removal, the temperature
of the system should not be lower than 10°C.
• A proper vacuum procedure is even more im-
portant with HFC and polyolester lubricant than
it has "traditionally" been with HCFC (R22) or
CFC and mineral oil.
For further details, please refer to TI bulletin
1-026.
Do not use a megohmeter or apply power to
the compressor while it is under vacuum, as this
may cause motor winding damage (motor burn-
out).

7 - Electrical connections

Make sure the main power supply to the sys-
tem has been switched off and isolated, in ac-
cordance with applicable regulations, before
performing any electrical connection.
Refer to Figs. 7, 8, 9 for wiring connection de-
tails with respect to the various motor codes.
Note that Performer® compressors SM/SZ 115
- 125 - 160 - 175 - 185 are provided with a bime-
tallic single pole single throw thermostat which
is located in the motor windings. Because the
thermostat is an automatic reset device, it must
be wired in a lockout safety circuit with a manual
reset to restart the unit (refer to Fig. 8). For over-
current protection, an external manual reset
overload protector must be used.
Note that Performer® compressors SM/SZ 084
- 090 - 100 - 110 - 120 - 124 - 147 - 148 - 161 and SH
090 - 105 - 120 - 140 - 161 are protected against
overheating and overloading by an internal sa-
fety motor protector. However, an external ma-
nual reset overload protector is recommended
for protecting the circuit against over-current
(Fig . 7).
SH/SY/SZ 240 - 300 - 380 motors are protected
by an external module protecting against phase
loss/reversal, overheating and high current draw
(Fig. 9).
The SH 180 motor is protected by a external
module protecting against overheating and
high current draw (Fig 10).
The "must trip" value of these overload relays
must be set in accordance with power line sizing
and design and shall never exceed the "A max."
value stamped on the nameplate.
Performer is a unidirectional machine and will
only pump refrigerant when properly phased.
The SM/SZ 084 to 185 and the SH 180 compres-
sors incorporate an internal reverse rotation
protection to safeguard the compressor. If rever-
se rotation occurs, shut the compressor down
and connect phases to the proper terminals. If
reverse rotation is not halted, the compressor
will cycle off on the internal motor protection.

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