Instructions
minals for the power connection. Fasten with
3 Nm torque.
• The thermostat connection (if present) is a ¼”
AMP-AWE spade connector.
• The compressor must be connected to earth
with the 5 mm earth terminal screw.
8 – Filling the system
• Keep the compressor switched off.
• Fill the refrigerant in liquid phase into the
condenser or liquid receiver. The charge must
be as close as possible to the nominal system
charge to avoid low pressure operation and ex-
cessive superheat. Never let the pressure on LP
side exceed the pressure on HP side with more
than 5 bar. Such pressure difference could
cause internal compressor damage.
• Keep the refrigerant charge below the indica-
ted charge limits if possible. Above this limit;
protect the compressor against liquid flood-
back with a pump-down cycle or suction line
accumulator.
• Never leave the filling cylinder connected to
the circuit.
Compressor models
Refrigerant charge
limit (kg)
SM/SZ 084, 090, 100
8.5
SM/SZ 110, 120
10
SM 112, 124, 147, SZ147
7.9
SM/SZ 115, 125
11
SM/SZ 148, 160, 161
12.5
SM/SZ 175, 185
13.5
SY/SZ 240
16
SY/SZ 380
20
SH / WSH 090
5.9
SH / WSH105, 120, 140,
161, 184
7.9
SH 180, 240, 295, 300
13.5
SH 380
14.5
SH 485
17
9 – Verification before commissioning
Use safety devices such as safety pressure
switch and mechanical relief valve in com-
pliance with both generally and locally appli-
cable regulations and safety standards. Ensure
that they are operational and properly set.
Check that the settings of high-pressure
switches and relief valves don’t exceed the
maximum service pressure of any system com-
ponent.
• A low-pressure switch is recommended to
avoid vacuum operation. Minimum setting
for SM/SY/SZ: 0.5 bar g. Minimum setting for
SH / WSH: 1.5 bar g.
• Verify that all electrical connections are pro-
perly fastened and in compliance with local
regulations.
•
When a crankcase heater is required, it
must be energized at least 12 hours before
initial start-up and start-up after prolonged
shutdown for belt type crankcase heaters (6
hours for surface sump heaters).
10 – Start-up
• Never start the compressor when no refrige-
rant is charged.
• All service valves must be in the open position.
• Balance the HP/LP pressure.
•
Energize the compressor. It must start
promptly. If the compressor does not start,
check wiring conformity and voltage on ter-
minals.
• Eventual reverse rotation can be detected
by following phenomena; the compressor
doesn’t build up pressure, it has abnormally
high sound level and abnormally low power
consumption. In such case, shut down the
compressor immediately and connect the
phases to their proper terminals. Most Dan-
foss scroll compressors are protected against
reverse rotation either by an internal reverse
rotation protection or by the external elec-
tronic protection module. They will shut off
automatically. Only SH / WSH 090 to 184 and
SM 112, 124, 147, SZ147 have no reverse rota-
tion protection. Prolonged reverse rotation
will damage these compressors.
• If the internal overload protector trips out (SM/
SZ 084, 090, 100, 110, 112, 120, 124, 147, 148,
161 and SH / WSH 090, 105, 120, 140, 161, 184),
it must cool down to 60°C to reset. Depending
on ambient temperature, this may take up to
several hours.
• If the internal pressure relief valve is opened
(SY/SZ 240, 300, 380 and SH 380, SH 485), the
compressor sump will be warm and the com-
pressor will trip out on the motor protector.
11 – Check with running compressor
• Check current draw and voltage.
• Check suction superheat to reduce risk of
slugging.
• Observe the oil level in the sight glass for
about 60 minutes to ensure proper oil return
to the compressor.
• Respect the operating limits.
• Check all tubes for abnormal vibration. Move-
ments in excess of 1.5 mm require corrective
measures such as tube brackets.
• When needed, additional refrigerant in liquid
phase may be added in the low-pressure side as
far as possible from the compressor. The com-
pressor must be operating during this process.
• Do not overcharge the system.
• Never release refrigerant to atmosphere.
• Before leaving the installation site, carry out
a general installation inspection regarding
cleanliness, noise and leak detection.
• Record type and amount of refrigerant charge
as well as operating conditions as a reference
for future inspections.
12 – Maintenance
Internal pressure and surface temperature
are dangerous and may cause permanent injury.
Maintenance operators and installers require
appropriate skills and tools. Tubing temperature
may exceed 100°C and can cause severe burns.
Ensure that periodic service inspections to
ensure system reliability and as required by local
regulations are performed.
To prevent system related compressor problems,
following periodic maintenance is recommended:
• Verify that safety devices are operational and
properly set.
• Ensure that the system is leak tight.
• Check the compressor current draw.
• Confirm that the system is operating in a way
consistent with previous maintenance re-
cords and ambient conditions.
• Check that all electrical connections are still
adequately fastened.
• Keep the compressor clean and verify the ab-
sence of rust and oxidation on the compres-
sor shell, tubes and electrical connections.
13 - Warranty
Always transmit the model number and serial number
with any claim filed regarding this product.
The product warranty may be void in following cases:
• Absence of nameplate.
• External modifications; in particular, drilling,
welding, broken feet and shock marks.
• Compressor opened or returned unsealed.
• Rust, water or leak detection dye inside the
compressor.
• Use of a refrigerant or lubricant not approved
by Danfoss.
• Any deviation from recommended instruc-
tions pertaining to installation, application or
maintenance.
• Use in mobile applications.
• Use in explosive atmospheric environment.
• No model number or serial number transmit-
ted with the warranty claim.
14 – Disposal
Danfoss recommends that compressors
and compressor oil should be recycled
by a suitable company at its site.
Danfoss can accept no responsibility for possible errors in catalogues, brochures and other printed material. Danfoss reserves the right to alter its products without notice. This also applies to products already on
order provided that such alterations can be made without subsequential changes being necessary in specifications already agreed.
All trademarks in this material are property of the respective companies. Danfoss and the Danfoss logotype are trademarks of Danfoss A/S. All rights reserved.
FRCC.EI.003.A6.02 - January 2014
Copyright Danfoss Commercial Compressors - DSS - 01/14
