Water Connections: Water/Glycol-Cooled Models; Notes For Open-Circuit Applications; Notes For Closed-Circuit Applications; Figure 30 Recommended Drycooler Installation - Emerson Liebert CRV User Manual

7.3

Water Connections: Water/Glycol-Cooled Models

The unit must receive cooling water as follows:
• From an external cooling water source, in open circuit.
• Using a drycooler, in closed circuit.
1. Connect the piping as shown in 5.2 Refrigeration and Hydraulic Circuits.
2. Use hoses connected with three-piece joints to the condenser water inlet and outlet couplings.
3. Install a field-supplied16-20 mesh strainer on the water/glycol supply to the Liebert CRV. The
strainer is needed to prevent particles in the water from entering the unit's heat exchanger.
4. Place shutoff ball valves at the conditioner inlet and outlet to allow easy maintenance.
5. Install a water drain system at the lowest point in the circuit.
6. Fully drain the piping before connecting it to the air conditioner.
7.3.1

Notes for Open-Circuit Applications

• Use the unit with mains or well water. Do not use water from an evaporative cooling tower unless
the water hardness is controlled.
• The water pressure must be 29-145psi (2-10 bar). If water pressure is outside this range, contact
Emerson for technical support.
• The required water flow at different temperatures is available from Emerson.
• If water temperature is very low, insulate both pipes.
7.3.2

Notes for Closed-Circuit Applications

• Install a pump system calculated on the basis of the flow and total head of the system (see site
plan data) and controlled by the compressor running (see label on the Liebert CRV).
• Insulate both pipes.
• Very important: Add water and ethylene glycol to the circuit when the ambient temperature is
below 32°F (0°C); refer to the Liebert CRV technical data manual, SL-11978). Do not exceed the
nominal operating pressure of the circuit components.
• Bleed air out of the circuit.

Figure 30 Recommended drycooler installation

HTC
Shutoff Valve
Pump
Check Valve
Gauge
® ™
Liebert CRV
TS
TS
Thermostat
(*)
HTC
Variex (50Hz Opt.)
Safety Valve
Expansion Tank
Air Separator
Water Connections for Water/Glycol Units—600mm (24") Models
Disconnect
After Charge
Standby Pump
(optional)
Charge Group (Filter,
Reducer, Check Valve)
Filling Meter
Drain (at Lowest Point)
52
Fill
Water
Liebert
CRV