Electrical Connections; Piping Connections - Liebert Mini-Mate2 MMD24E User Manual

5.8.2

Electrical Connections

Refer to 5.5.5 - Electrical Connections for general wiring requirements and cautions. Refer to
electrical schematic when making connections. Refer to specifications for full load amp. and wire size
amp. ratings.
Control Connections
A 4-wire control connection is required from the evaporator unit to the condensing unit. Glycol cooled
units also require a two-wire control connection to the drycooler and pump package.
5.8.3

Piping Connections

Details for refrigerant (R-407C) loop piping are in 5.5.3 - Piping Connections and Coolant
Requirements.
Water/Glycol Piping Considerations
Manual service shutoff valves should be installed at the supply and return line to each unit. This
enables routine service and/or emergency isolation of the unit. When the condensing unit fluid quality
is poor, filters that can be easily serviced should be placed in the supply line. These filters extend the
service life of the condensing unit.
Condensing Unit Fluid Requirements
The maximum fluid pressure is 150 PSI standard pressure and 350 PSI for high pressure units (refer
to unit nameplate and model number description page at beginning of this manual). The water cooled
system will operate in conjunction with either a cooling tower or city water. Glycol cooled systems will
operate in conjunction with a cooling tower, city water, or drycooler.
Automotive anti-freeze must not be used in glycol systems. Prepare glycol solution using customary
practices.
Regulating Valve
Water/Glycol cooled units include a coolant flow regulating valve which is factory adjusted and should
not need field adjustment.
Standard pressure and high pressure valves are adjusted differently. Contact Emerson Network
Power Liebert Services before making any adjustments.
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Liebert Mini-Mate2 38
Site Preparation and Installation