Unit installation

IOMM ACZ/AGZ-3 ACZ / AGZ-BM 99
High Ambient Limit
On units not configured with multi-point power connections, the maximum load amps could be
exceeded at high ambient temperatures. If all circuit 1 compressors are running or all but one
compressor on circuit 1, power connection is single point, and the OAT is greater than 116°F, circuit
2 is limited to running all but one compressor. The circuit 2 status will indicate if this is the case.
This action will allow the unit to operate at higher temperatures than 116°F.
Unit Capacity Overrides
The following conditions override the automatic capacity control when the chiller is in COOL mode
only.
Demand Limit
The maximum unit capacity can be limited by a 4-to-20 mA signal on the Demand Limit analog
input. This function is only enabled if the Demand Limit setpoint is set to ON. The maximum unit
capacity stage is determined as shown in the following graphs:
1
2
3
4
0.0 25.0 50.0 100.075.0
Max
Stage
3
4
5
6
0 16.7 66.7 83.350.0
Limit Signal (%)
Max
Stage
33.3 100.0
2
1
0
Limit Signal (%)
Limit Signal vs. Max Stage
(with 4 compressors)
Limit Signal vs. Max Stage
(with 6 compressors)