Emerson DE, VH, VE, DH manual System Description, Introduction

Introduction

1.0INTRODUCTION

1.1System Description

Liebert Deluxe environmental control systems are available in several configurations. Each configu- ration can operate with either Advanced Microprocessor Controls (AM), or Advanced Microprocessor Controls with Graphics (AG). A brief description of each, including operational differences, are listed below. Check model numbers to see what is supplied with your unit.

1.1.1Compressorized Two-Step Systems

These systems may be air, water, or glycol cooled - depending on the heat rejection method selected.

Cooling

Two stages of mechanical refrigeration

Heating

Three stages of electric reheat standard; steam/hot water, hot gas on water and glycol-cooled systems optional

Humidification

Infrared standard, steam grid and steam generating optional

Dehumidification

Utilizes the lag compressor

1.1.2Compressorized Four-Step Systems

The 4-stage systems have all the features of a compressorized 2-stage system plus cylinder unloaders on one head of each compressor. This permits the compressors to operate at a reduced level and increases energy efficiency during low load conditions. The system responds to an increasing room load with either a two step or a four step process of increasing the unit's cooling.

Cooling

Four stages of mechanical refrigeration:

1.Lead compressor at reduced capacity.

2.Lead and lag compressors at reduced capacity.

3.Lead compressor at full capacity; lag compressor at reduced capacity.

4.Lead and lag compressors at full capacity.

Heating

Three stages of electric reheat standard; hot water/steam optional

Humidification

Infrared standard, steam grid and steam generating optional

Dehumidification

Utilizes the lag compressor

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