Operator Responsabilities; Start-Up Preliminary Procedures - Trane Flex II Original Instructions Manual

10 USER RESPONSABILITIES
It is important that the operator is properly trained and familiar with the equipment before working on the unit. In
addition to reading this manual, the operator must study the manual operation of the microprocessor and the wiring
diagram to understand the sequence of start- up, operation, shutdown sequences, and the criterion of operation of all
safety devices. During the initial start-up of the unit an authorized technician is available to answer any questions and
educate on the proper functioning. We recommend the operator to maintain a record of the operating data for each
unit installed and all maintenance activities and periodic service. If the operator observes abnormal or unusual
operating conditions, consult the authorized service technician.

11 START-UP PRELIMINARY PROCEDURES

11.1 STARTING CHECK
Before starting the unit, even only momentarily, all the equipment connected to the chilled water, like the air handling
units, pumps, etc. have to be checked. The pump auxiliary contacts and the flow switch have to be connected to the
control panel as indicated in the electrical diagram. Before carrying out interventions on the valve regulations, loosen
the relevant valve gland. Open the discharge valve of the compressor. Open the liquid shutoff valve placed on the liquid
line. Measure the suction pressure. If it is lower than 0.42 MPa jumper and strain the solenoid valve on the liquid line.
Bring the suction pressure to 0.45 MPa, then remove the jumper. Charge all the water circuit progressively. Starts up
the water pump of the evaporator with the calibration valve shut and then slowly open it.
Discharge the air from the high points of the water circuit and check the direction of the water flow. Carry out a setting
of the flow by using a measurer (if present or available) or by means of a combination of the readings of the
manometers and the thermometers. In the starting phase set the valve on the pressure difference read on the
manometers, carry out drainage of the tubes and then carry out fine setting on the temperature difference between the
water in and the water out. The regulation is set in the factory for water in to the evaporator at 12°C and water out at
7°C. With the general switch open, check that the electrical connections are tightly clamped. Check for any possible
refrigerant leaks. Check that the electrical data on the label correspond to those of the mains supply. Check that the
thermal charge available is appropriate for starting.
11.2 REFRIGERANT SEALS CONTROL
Units are sent with the complete charge of refrigerant and are at a sufficient pressure to check the seal after installing.
If system if not under pressure, remove remaining refrigerant with recovery system. Charge the system with dry
nitrogen to find the leak(s). Repair the leak.
After having eliminated the leakage, the system has to be dehydrated with a vacuum pump up to at least 1mm Hg -
absolute pressure (1 Torr o 133.3 Pa). This is the minimum recommended value to dehydrate the plant.
WARNING! Do not use the compressor to vacuum the system.
11.3 REFRIGERANT CHARGE CHECK
Units are supplied with a complete charge of refrigerant. If bubbles can be seen through the peephole with the
compressor running with a full charge and steadily, it means that the refrigerant charge is insufficient