Compressor Sequence Operation; Starting Sequence Condition - Fujitsu Airstage VR-II Series Service Manual

2-4-4 Compressor Sequence Operation

Make starting sequence and start and stop of the compressors in accordance with
the below sequence.

Starting sequence condition

Example)
Starting sequence
Starting sequence
Starting sequence
Rotate the stating sequence under the following conditions:
(1) Defrosting
(2) Oil recovery
(3) When cooling discharge temperature is high
(4) After stopping from Heating operation / Heating main operation
Run command
INV INV
INV
INV
INV INV
INV INV
INV
INV INV
INV
INV
INV INV
INV
INV INV
INV INV
INV
: Compressor started first, compressor stopped last
: Compressor started 2nd, compressor stopped 2nd from the end
: Compressor started 3nd, compressor stopped 3nd from the end
Starting rotation
execution
INV INV
Stop
INV INV
Start
INV
INV
Start
INV
INV
Stop
Oil recovery
Stop
Starting rotation
execution
INV INV
Stop
INV
INV
Stop
02-06
INV
Stop
INV
Start
INV
Start
INV
(example)
Stop
INV
Start
INV
Start
Stop Compressor
Operation Compressor
INV INV
INV
INV
INV INV
INV INV
INV
INV INV
INV
Start
Stop
Stop
Stop