McQuay M4MC075D, Owner'S Manual

Page: 5 / 177

4
General Specifications
Unit Structure
The casing is constructed with electro-galvanised (EG) mild steel sheet which provide a rigid cabinet. The
thickness of the indoor casing is ranging from 1.0mm to 3.2mm whereas the outdoor casing thickness is
ranging from 1.0mm to 2.3mm. The finishing of the casing is a long-lasting epoxy polyester powder coating.
The indoor panel is using PE insulation with 10mm thickness. All outdoor units are classified under the IP55
Standard.
Coil
Each coil consists of staggered rows of 3/8” OD seamless copper tubes, mechanically expanded into die-
formed corrugated aluminum fins. All coils are using aluminum fin except heatpump models which are using
hydrophilic blue fin to have better deicing during defrost cycle.
Blower, Fan And Motor
The indoor unit is using metal blower with the forward-curved fan blade and secured by the metal housing.
The outdoor propeller fan is constructed from 6-blade aluminum material and direct-driven by weatherproof
three phase induction motor. All motor has the Class F (155
°
C) insulation.
Compressor
All outdoor units are using high efficiency, refrigerant-cooled, Scroll compressor. Compressor has the
internal overload protection and supplied with crank case heater to prevent liquid migration, which can
damage compressor scroll, during off-cycle and eases start-up.
Safety Controls
Outdoor units are equipped with auto reset high pressure and low pressure cut-out and discharge thermostat
(heatpump only) to protect against compressor damage due to high head pressure and system leakage
respectively. Phase protector is used to detect for any wrong phase and phase loss during installation and
operation.