AEC ACOA Series Air-Cooled Central Chillers - Manual (Page 36)

9. Set the controller to the entering temperature you want. Check the temperature of the
process water in and out to be sure the unit is operating within the desired temperatures
you have selected.
5-4 Lubricating the Compressor
Oil Pump
Note: Only a qualified service person should check oil pressure.
During operation, watch the oil through the sight glass to verify that the oil is being agitated,
which indicates that the oil pump is working. If you have any doubt about oil pump operation,
check oil pressure by installing a gauge in the ¼” tapped pump cover opening. Oil pressure
should be 30-45 psi (207-310 kPa) above suction pressure.
If oil pressure is insufficient:
1. Try reversing the rotation direction on the compressor. The compressor can operate in
either direction.
2. If reversing doesn’t work, check for a plugged oil strainer.
3. If the strainer is clean, replace the complete pump end plate assembly, not just the pump.
Oil Type
If the oil becomes discolored, indicating contamination, install a new filter-dryer in the liquid
line and change the oil. The amount of oil needed for each compressor is listed in Figure 1 on
Page 9.
Caution!
Use only Type 150SUS Calumet R015 or Texaco WF-32 refrigeration oil.
Do not use any other oil, or your warranty is voided!
5-5 System Flow Rate
You can estimate the quantity of chilled water being circulated by determining the water
pressure drop through the evaporator, and reading the flow rate in gallons (liters) per minute
from the appropriate pressure drop curve in Figure 18 on the following page.
An alternate method of determining flow rate is to measure pressure difference from pump inlet
to outlet and read the flow rate from the pump curve.
Water flow rates must not vary more than plus or minus ten percent (±10%) from design flow
rates.
ACOA Series Air-Cooled Central Chillers
Page 35