
AGL_Stream_ST_A2L_A1_4M_6M_EN_Rev00
7
Assembly
Installation of the modified cylinder head and valve plate for unloaded start is only possible on certain
positions on the compressor. Therefore all 4M* and 6M* compressor models have fixed cylinder head
positions for unloaded start.
Figure 4: Unloaded start position 4M*
Figure 5: Unloaded start position 6M*
NOTE: The operation of the unloaded start can also be controlled by the Copeland
compressor electronics module (dedicated extension module D to be ordered).
2.5.5 Capacity control
WARNING
Ignition source in a potentially flammable atmosphere! Fire hazard!
The
solenoid valve of the capacity control is not an ignition source during normal
operation in an A2L-refrigerant system but could become one if not installed
properly. Never operate the solenoid coil when not positioned on the solenoid
valve. Secure the installation with a screw.
A mechanical capacity control is available for 4M* and 6M* compressors. The system used is blocked
suction. The suction port of the valve plate will be closed by a control piston. When a compressor is
ordered with capacity control, it is equipped with one (4M* models) or two (6M* models) special
cylinder heads. The capacity control valves with coils are positioned on the top of the cylinder head.
Not all cylinder bank positions are possible for the capacity control cylinder head.
Capacity control must be fitted in the following positions:
4M*
50 %
Terminal box side
6M* 1
st
step
33 %
Upper cylinder head
6M* 2
nd
step
66 %
Terminal box side
Figure 6: Capacity control position 4M*
Figure 7: Capacity control position 6M*