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INITIAL START-UP
After all the other preceding checks have been completed and the operator has familiarized himself with the
sequence of operation for the unit and all options provided, the unit can be put in operation. Proceed as follows:
1. Energize cooling tower water pump and tower fans. Set the water flow rate according to the design value.
2. Turn ON the MCB/MCCB (MCB single pole for control circuit, MCB three poles for power supply for three
phase motor) and press button "START" on the unit LCD wall pad.
3. If no abnormal noise or adverse conditions exist allow the unit to run. If these conditions does exist, turn off the
unit and investigate possible causes by taking below steps:
i) Check for correct power phasing to unit. Correct rotation on scroll compressor can be determined by a drop in
suction pressure and a rise in discharge pressure when the compressor is energized. To reverse the rotation on a
three phase scroll compressor, simply swap connection of any two of the three compressor phases at the
power supply terminal and recheck operating pressures. Running the compressor for a short period of time in
reverse direction will have no negative impact but prolonged running in reverse direction may cause premature
failure.
*UCQ60/90/140/180/320/360/400/520*E is supplied with external Supply Monitoring Device factory
preset: UV 90%, OV 5%, On Delay 1 Second, Off Delay 5 Second (Fixed).
* UCQ240/280/570/710/870/940, the motor protection module comes preinstalled within the
compressor terminal box. The module had been terminated at control box of unit.
ii) Check for correct direction for air discharge (only apply to blower motor changed to opposite direction from
original position). Simply swap any two of the three wires at the power supply inlet to fan contactor terminal.
Incorrect wiring or blower rotation may trigger on the fan overload protector.
iii) Check for belt tensioning
4. Once the unit is run normal, take an air flow measurement in the straight duct off the unit discharge using a pitot
tube. This measurement should be taken about three quarters (3/4) of the way down the straight duct off the fan, just
before any transition or elbow. If a condition of low or high air flow exists, a pulley change may be required.
Once it is ascertained that the air quantity leaving the unit is according to the design CFM, the thermostats should be
set to the desired space temperature. The system should now function as designed.
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