AEC Econo-Cool Chillers - Manual (Page 23)

Page 22 AEC Water Temperature Control Units
Water Out
Size Depends on Solenoid Used
The cooling water outlet leading back to the cooling tower, chiller, or drain.
Net supply pressure must be between 25 psig and 55 psig (172.38 kPa/1.72 bars and
379.2 kPa/3.79 bars). Net supply below 15 psig (103.43 kPa/1.03 bars) may allow
water to flash to steam, cavitate the impeller, and damage the pump, which prevents
the unit from cooling properly. Operation above 55 psig (379.2 kPa/3.79 bars) may
cause premature opening of the relief valve from pump pressure and pressure surges.
PRESSURE RELIEF — ¾”
The pressure relief valve, located at the back of the unit, is pre-piped to approximately
four inches (4” or 10 cm) above the floor. This piping reduces the chance of scalding
nearby personnel if the relief valve should trip.
3-9 Making System Purge Connections
Economical Series systems equipped with the System Purge option have a compressed
air inlet marked
MOLD PURGE . Connect to a clean, dry 100 psig (689.50 kPa/6.90
bars) air line. Install your own shutoff valve to prevent process liquid from backing up
into the plant air piping if the compressed air is turned off and the check valve fails.
Don’t depend on the solenoid valve to hold water pressure in the temperature
control unit.