Johnson Controls L-Series User Manual

FORM 145.05-EG2 (618)
78
JOHNSON CONTROLS
economizer alone is insufficient for load.
• Condenser Water Control Sequences Built-In
1. No Condenser Valves
2. Condenser Valve Only – No Bypass
3. Condenser Valve With Bypass Valve
4. Condenser Valve With Water Economizer Valve
• Hot Water or Steam Control Sequences (Proportional)
• Staged Heat Sequences (4 Stages)
AUXILIARY CONTROL OPTIONS
Non-Fused Disconnect
A factory installed non-fused disconnect switch shall be provided for disconnecting elec-
trical power at the unit. The switch shall be located at the front of the unit, visible and
accessible without removing any access panels.
Dual Power Block
Factory installed two power terminal blocks shall power the supply fan and controls from
one power distribution block and power compressors and optional electric heat from a
second power distribution block. This arrangement shall allow operation of fan only when
that power distribution block is energized.
Dual Non-Fused Disconnects
Two factory installed non-fused disconnect switches shall be provided for disconnecting
electrical power at the unit. One shall be sized for the controls and supply air fan motor.
The other shall be sized for all the compressors. The switches shall be located at the front
of the unit, visible and accessible without removing any access panels.
Phase Failure/Under Voltage Protection
A phase failure/under voltage protection device shall be provided to protect three-phase mo-
tors from damage due to single phasing, phase reversal and low voltage conditions.
Freezstat
A non-averaging type freezstat is factory mounted at the unit’s entering face of the coil.
When a temperature is sensed on any 18" of the freezestat below 38.0°F, an alarm signal
shall be generated, the fan will shut down, and the waterside economizer [heating] [water-
side economizer and heating] valve shall be driven to 100% open to allow full flow. This
alarm requires a manual reset.
Head Pressure Control with One Two-Way Valve
When the entering condenser water temperature is below 55.0°F and/or the use of wa-
terside economizer is not available, a factory installed and controlled modulating head
pressure control two-way valve shall be provided. The valve actuator shall be controlled
through the factory installed main unit control system to maintain refrigerant head pres-
sure by reducing the water flow as necessary to allow proper functioning of thermostatic
Guide Specifications (Cont’d)

Johnson Controls L-Series Specifications

General

Brand	Johnson Controls
Model	L-Series
Category	Air Conditioner
Language	English