-6- 55008386-05
PIPE CONNECTIONS/RESTRICTORS
1.
Outdoor units are supplied with the following brazed connections (sizes in inches);
Model
Size
MCU+
180 - 200
Expansion
1/2
Suction
7/8
NOTE:
Ensure that both service valves on the outdoor unit are closed (IN, fully clockwise) before commencing installation.
Indoor units have a low pressure holding charge of nitrogen, which may be released into the atmosphere without damage to the
environment. This should be done prior to making pipework connections.
2.
Intdoor units are delivered with thermal expansion valve fitted.
ELECTRICAL CONNECTIONS
Mains, control and interconnecting cables must be supplied and fitted by the installer.
Installer wiring must be carried out in accordance with local and national codes.
Mains supply cables must be size compatible with the recommended fuse for a given system).
An all pole isolator switch should be positioned within easy reach of the indoor unit.
The equipment must be earthed.
Cable clamps for use with stranded cables should be used to secure all incoming/outgoing cables.
Installers must supply a method of securing any solid sheathed cables.
Systems require a supply to the outdoor/ducted unit with connecting cables run to the indoor unit.
SCROLL COMPRESSOR ROTATION
On 3 Phase units it is possible for the scroll compressor to run backwards. This becomes obvious on start up; the compressor will not
develop a normal running pressure differential and the top will not become warm. It may be excessively noisy. If this happens, switch off
the mains power and exchange any two of the phases supplying the unit. This will correct the rotation of the compressor.
OUTDOOR UNIT WIRING
Cable entry for the outdoor unit electrics is through the cabinet access panel to a terminal block.
MCU+
units are supplied wired via a head pressure controller to give maximum control. Ensure that all connections are secure and that
both units are earthed.
DATA PLATES
Because of the ability to mix-match indoor and outdoor units, the data plate only gives information on outdoor units. To obtain the
system details, input power and currents from indoor and outdoor units should be added together. Data plates show basic units with
electric heater kit loads shown separately.
EVACUATING
Connect a vacuum pump to the service ports on the outdoor unit valves and evacuate the interconnecting pipework and indoor unit to
1000 microns (1 Torr) or better and allow to be held for a minimum of 15 minutes.
