Vertiv Liebert Mini-Mate2 MMD24E Technical Data Manual page 75

2.2 DIRECT EXPANSION SYSTEM EVAPORATOR COMPONENTS
2.2.1 Direct Expansion Coil
The evaporator section shall include evaporator coil, thermostatic expansion valve and filter drier.
The evaporator coil shall have 3.1 sq. ft. (0.29 sq.m) face area, 3 rows deep. It shall be constructed of
copper tubes and aluminum fins and have a maximum face velocity of ____ fpm (m/s) at ____ CFM
(CMH). An externally equalized thermostatic expansion valve shall control refrigerant flow. The
evaporator coil shall be factory-charged with R-407C refrigerant and sealed. The evaporator unit can be
coupled directly with a ceiling mounted condensing unit or mounted remote to the condensing unit.
The coil assembly shall be mounted in a condensate drain pan with an internally trapped drain line. The
evaporator drain pan shall include a factory-installed float switch to shut down the evaporator upon high
water condition
2.2 CHILLED WATER SYSTEM COMPONENTS
2.2.1 Chilled Water Control Valve
The control valve shall be a motorized, slow-close On/Off type to reduce water hammer. Design pressure
shall be 300 psig (2068 kPa) static pressure, with a maximum close-off pressure of 60 psig (414 kPa).
Valve shall be non-spring return.
2.2.2 Chilled Water Coil
The cooling coil shall have a minimum of 3.1 sq.ft. (0.29 sq.m) face area, 3 rows deep. It shall be
constructed of copper tubes and aluminum fins and have a maximum face velocity of 391 fpm (2.0 m/s)
at 1250 CFM (2124 CMH). The coil shall be supplied with 45°F (7.2°C) entering water temperature. The
coil shall be supplied with ______ GPM (l/s) of chilled water and the pressure drop shall not exceed
______ PSI (kPa).
The coil assembly shall be mounted in a condensate drain pan with an internally trapped drain line. The
evaporator drain pan shall include a factory-installed float switch to shut down the unit upon high water
condition.
2.3 INDOOR AIR-COOLED CENTRIFUGAL FAN CONDENSING UNIT
Condensing unit components shall include condenser coil, scroll compressor, high-pressure switch,
® ™
Liebert Lee-Temp refrigerant receiver, head pressure control valve, hot gas bypass system and liquid
line solenoid valve. The cabinet and chassis shall be constructed of heavy gauge galvanized steel, and
shall be serviceable from one side. Mounting brackets shall be integral to the cabinet design and be
designed for ceiling mounting.
The hot gas bypass circuit shall be provided to reduce compressor cycling and improve operation under
low-load conditions. The hot gas bypass shall be completely contained in the condensing unit. Field
installed third refrigerant line shall not be acceptable. Hot gas bypass shall be automatically deactivated
upon a call for dehumidification.
High pressure switch shall protect the unit from abnormal refrigerant pressure conditions and shall
deactivate the compressor and annunciate an alarm at the wall controller. The blower shall continue to
circulate air. The wall controller shall be used to manually restart the compressor function after the
automatic pressure switch resets. Three high head pressure alarms in a rolling 12-hour period shall lock
out the manual restart feature until power is cycled to the evaporator unit.
A pressure balancing valve shall be factory installed to reduce the chance of high pressure cut-out due to
excessive refrigerant migration to the receiver due to changing outdoor temperatures during off-cycles.
SL-10535a_ REV5_2-17
Liebert Mini-Mate2—2- and 3-Ton
5 Guide Specifications