LG MULTI F Engineering Manual page 14

MULTI F WITH LGRED
Multi F with LGRED Heat Pump Units
General
A Multi F with LGRED multi-zone system is comprised of one heat
pump outdoor unit connected to two, three, or four indoor units using
a shared refrigerant piping circuit between the outdoor unit and
each indoor unit, and includes integrated controls supplied by LG.
The outdoor unit is internally assembled, wired, and piped from the
factory; all LG components are manufactured in a facility registered
to ISO 9001 and ISO 14001, set by the International Organization for
Standardization (ISO). The LG Multi F with LGRED multi zone heat
pump system components comply with Underwriters Laboratories
(UL) 1995 Heating and Cooling Equipment Standard for Safety, and
bear the Electrical Testing Laboratories (ETL) mark. The units are
certified to AHRI 210 / 240.
Temperature Ranges
The heat pump outdoor units are capable of operating in cooling
mode from 14°F to +118°F ambient dry bulb (installing an optional
Low Ambient Wind Baffle Kit will allow operation down to -4°F in
cooling mode. The heat pump outdoor units are capable of operat-
ing in heating mode from -13°F to +75°F ambient dry bulb without
additional low ambient controls.
Frame
The Multi F with LGRED condensing unit case is constructed from
pre-coated metal that has been tested in accordance with ASTM
B-117 salt spray procedure for a minimum of 1,000 hours. Case has
a removable front panel to allow access to major components and
control devices, and legs to secure the unit during installation.
Refrigerant System
Multi F with LGRED systems have a shared refrigerant circuit field
piped to multiple (ducted, non-ducted or mixed) indoor units to effec-
tively and efficiently control the heating or cooling operation of the
multi zone system. All refrigerant lines from the outdoor unit to the
indoor units are field-installed and must be insulated separately.
All Multi F with LGRED systems use R410A refrigerant. The outdoor
units are equipped with a refrigerant strainer, check valves, oil
separator, accumulator, four-way reversing valve, electronic ex-
pansion valve(s) (EEV), high side and low side refrigerant charging
ports, and a service port. Each outdoor unit also includes sensors
for suction temperature, discharge temperature, high-pressure,
low-pressure, heat exchanger temperature, and outdoor temperature
conditions.
Refrigeration Oil Control
The outdoor units have an oil separator to separate oil mixed with
the refrigerant gas during compression and return oil to the com-
pressor. The outdoor units also have an oil injection mechanism to
ensure a consistent film of oil on all moving compressor parts at low
speed.
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Compressor
Multi F with LGRED con-
densing units are equipped
with one hermetically sealed,
digitally controlled, inverter
driven twin-rotary compressor
that includes Teflon™ coated
bearings. The inverter motor is
capable of providing a modu-
lation range of 20Hz to 100Hz
with control in 1Hz increments.
The compressor is protected
with phase-reversal protec-
tion, uses a factory-charge
of Polyvinyl Ether (PVE) oil,
and is mounted to avoid the
transmission of vibration.
Fan and Motors
Each outdoor unit includes
one direct drive variable speed
propeller fan with Brushless
Digitally Controlled (BLDC)
motor with a horizontal air dis-
charge. Fan blades are statically and dynamically balanced propeller
fans made of durable Acrylonitrile Butadiene Styrene (ABS) plastic,
and include a raised fan guard to limit contact with moving parts. The
motors have inherent overload protection, permanently lubricated
bearings, and a maximum speed up to 950 rpm. All Multi F outdoor
units have a horizontal discharge airflow.
Outdoor Unit Coil
The outdoor unit coils are factory-built of aluminum fins mechanically
bonded on copper tubing. Coils have a minimum of two rows, a mini-
mum of 14 fins per inch, and have been factory pressure-tested.
Coil fins also have a factory applied corrosion-resistant GoldFin™
material with hydrophilic coating that has been tested in accordance
with ASTM B-117 salt spray test procedure for a minimum of 1,000
hours.
Electrical
All Multi F with LGRED outdoor units shall have 208/230V, 1 phase,
60Hz electrical power capable of operating within ±10% of the rated
voltage.
Controls
Factory installed microprocessor controls in the outdoor unit and
indoor units shall perform functions to efficiently operate the multi-
zone system. System wiring must be installed in a tree configuration
from outdoor unit to indoor units through four conductor power/
transmission cable. The system is capable of performing continuous
operation, even when power is turned off to an individual indoor unit.
F
MULTI
WITH
Figure 4: Dual-Zone (LMU180HHV)
Multi F with LGRED System.