Liebert 138401P1S Enthalpy Control for HVAC Economizer Systems

The Liebert 138401P1S is an enthalpy control designed for use in precision air conditioning economizer systems. This control measures both temperature and humidity in outdoor air to determine optimal conditions for free cooling operation, helping reduce energy consumption in commercial HVAC applications.

Key Features:

• Monitors outdoor air enthalpy (total heat content) for economizer operation
• Integrates with Liebert precision cooling systems and economizer assemblies
• Helps determine when outdoor air conditions are favorable for free cooling versus mechanical cooling
• Two-position SPDT (Single Pole Double Throw) switching for system control
• Duct mount installation for accurate air measurement
• Factory authorized Liebert replacement part ensuring exact specifications

Enthalpy controls provide more accurate economizer operation than simple temperature-based controls by accounting for both temperature and humidity levels. This ensures the system only uses outdoor air when conditions truly provide energy-efficient cooling. Commonly used in data centers, server rooms, and critical environment cooling systems where Liebert precision air conditioners are installed.