Operating instructions

Start-up

Pre Start-up

The unit must be inspected to see that no components became loose or damaged during shipping or

installation.

Start-Up

There should be adequate building load (at least 50 percent of the unit full load capacity) to properly

check the operation of the unit’s refrigerant circuits.

Record all operating parameters required by the “Compressorized Equipment Warranty Form”.

Return this information within 10 working days to McQuay International as instructed on the form to

1. Verify chilled water or air-flow.

2. Verify that the remote start / stop or time clock has requested the chiller to start.

3. Set the thermostat setpoint to required temperature. For AGZ-AM units, the system water

temperature must be greater than the total of the leaving water temperature setpoint plus 1/2 the

control band before the MicroTech II controller will stage on cooling. Set the Evap Delta T and

the Start Delta T as a starting point.

4. Put both pumpdown switches (PS1 and PS2) to the ON position.

5. Put system switch (S1) to ON position.

Switch Position

Switch

ON OFF

PS1, PS2,

Pumpdown

Switches

Circuit will go through the

normal pumpdown cycle and

shut off.

Circuits will operate in the

normal automatic mode

Unit will shut off immediately

without pumping down

(emergency stop)

S1, Unit will operate in the

normal automatic mode

System Switch

6. There can be a delay of 2 minutes after closing S1. The time delay is due to the compressor

inherent motor protection or the Stage Up Timer counting. This should only occur on initial

start-up or when power to the chiller has been turned off and back on. More than one

compressor will not start at the same time.

7. After the chiller has been operating for a period of time and has become stable, check the

following:

Compressor oil level. (Some scroll compressors do not have oil sight glasses) 



Refrigerant sight glass for flashing.

Rotation of condenser fans.

8. Complete the “Compressorized Equipment Warranty Form”.

IMM ACZ/AGZ-4 ACZ / AGZ-BM 59