Start-Up Commissioning; Preparation Before Commissioning; Commissioning Procedures - Emerson Chilled Water Series User Manual

32 Chapter 4 System Start-Up Commissioning

4.2 Start-Up Commissioning

4.2.1 Preparation Before Commissioning

Mechanical and system part
1. Check that the protection materials during transportation have been removed;
2. Check that the motor pulley and the fan pulley are fixed, the motor bearing and fan bearing are parallel, the
belt is perpendicular to the two bearings and the tension of the belt is proper;
3. The pressure-leak detection of the chilled water system has been done and the chilled water system is
confirmed to be qualified;
4. The cleaning and emptying of the chilled water system have been done (air vent valve is located in the top
of the heat exchanger coil);
5. The chilled water system has been confirmed ready for operation;
6. The water supply-/drainage-pipe system of the humidification system has been reliably connected
according to the material requirements and has been checked against leakage;
7. Make sure the equipment room temperature is above 68°F with sufficient heat load. If the heat load is
insufficient, heat the equipment room with other heating devices, or by forcibly hand-running the heater of the
unit or adjacent other equipment (in this case, go through the following procedures till the third step of 4.2.2
Commissioning Procedures) to make sure the heat load is sufficient for the commissioning.
Electrical part
1. Check that the input voltage of the main power is -10% ~ +15% of the rating;
2. Check that all electrical or control cables are correctly connected. Fasten all the connecting terminals;
3. The power cables and the low voltage control cables are laid away from each other;
4. Check the phase sequence. The phase sequences of all three-phase devices have been adjusted consistent
before delivery. During commissioning, you only need to ensure the phase sequence of a random three-phase
device is correct. In step two of 4.2.2 Commissioning Procedures, you can use a straight screwdriver to click
on the fan contactor within the electric control box to judge the phase sequence by observing the wind
direction. If the phase sequence is wrong, exchange any two phases of the L line of the power supply.

4.2.2 Commissioning Procedures

1. Turn off the MCBs of various parts. Turn on the main MCB and control MCB and check the control voltage.
2. Switch on the fan MCB and click on the contactor of the indoor fan with a screwdriver to confirm the
rotation direction of the fan. Start the equipment and measure all the phase currents of the fan.
3. Switch on the electrical heater MCB and change the temperature setting to start the electric reheat, or start
the heater manually. Measure all the phase currents of electrical heater.
To trigger the electrical heater, you should:
Change the temperature setting (see 5.7 SERVICE MENUS) to 9°F higher than the indoor temperature. The
system should then trigger the call for heating and the electric reheat starts to work. Then set the temperature
setting to 9°F lower than the indoor temperature. If the electrical heater stops working, it means the heating
function is normal. Keeping the temperature setting can make no heating requirement. Continue the following
commissioning steps.
4. Switch on the humidification MCB and change the humidity setting to start the humidifier, or start the
humidifier manually. Measure all the phase currents of the humidifier. Manually charge water into the cooling
system to check that the charge-/drainage-pipes do not leak and the drainage pipes are clear.
To trigger the humidifier, you should:
Adjust the humidity setting (see 5.7 SERVICE MENUS) to 10% higher than the indoor relative humidity. The
control system should then trigger the call for humidification, and the humidifier starts to work. If the
humidifier stops working when the humidity setting is lower than the indoor relative humidity, it means the
humidifying function is normal.
 Note
After commissioning, restore the humidity setting to the default or the original setting.
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