Trane RAUL 190, Manual

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10 RAU-SVX01G-GB
Installation
Electrical connections
CAUTION!
1. The greatest care should be taken when cutting through passages and installing electric wiring. Under no
circumstances should chips of metal or cuttings of copper or isolating material fall into the starter panel or
electric components. Relays, contactors, terminals and control wiring should be covered and protected before
power supplies are connected.
2. Install power supply cabling as shown in wiring diagram. Adequate cable gland should be chosen, ensuring no
foreign bodies enter the electrical housing or components.
3. Cabling must comply with standards in force. The type and location of fuses must also comply with standards.
As a safety measure, fuses should be visibly installed, close to the unit.
4. Only copper wiring should be used. Using aluminium wires can produce galvanic corrosion and possibly lead to
superheat and failure of connection points.
As standard, Trane provides the single power supply which includes the transformer. Warranty reserves will be
formulated if a transformer, not supplied by Trane, is installed inside the electric panel.
Temperature sensor
Two temperature sensors are provided, in the control panel of the unit. They have to be fi tted on site in order to
measure the air inlet and outlet temperature downstream to the DX coil (evaporator). Refer to supplied wiring
diagram for connection of sensors.
To place the sensor into the airfl ow, the technician will have to cut the cable between the electronic case and the
sensing element, and then reconnect both elements with a twisted pair cable with a maximum distance of 300m.
Hot gas-bypass control (option)
The hot gas bypass option only provides a relay contact needed to initiate hot gas bypass on the evaporator.
All the refrigerant piping modifi cations are not done in the factory and have to be done on the jobsite. An additional
refrigerant line and solenoid valve must be added on site (not provided) between the discharge line and the suction
line on Circuit 1. When the solenoid valve is activated, refrigerant vapor will fl ow from the discharge line to the
suction line. This refrigerant vapor satisfi es the compressor mass fl ow requirement, but because no phase change
has occurred, this fl ow does not contribute to unit capacity. The amount of capacity shed by the hot gas bypass line
depends upon the size of the line (restriction) and the pressure difference between the discharge line and the suction
line. Closing the solenoid valve in the hot gas bypass line deactivates hot gas bypass.
Figure 3
1 = Air intake
2 = Fan
3 = Evaporating coil
4 = Air supply
5 = Evaporator leaving air temperature sensor 6 = Evaporator entering air temperature sensor
7 = Thermostatic expansion valve
8 = Sight glass
9 = Manual shut-off valve
10 = Filter dryer
11 = Liquid solenoid valve