AEC Econo-Cool Chillers - Manual (Page 46)

AEC Water Temperature Control Units Page 45
It is also fitted with high temperature flexible components for maximum heat
resistance. These same components remain flexible even at low temperatures. Thus, the
standard seal is a fine combination of heat resistant and wear resistant components.
Unfortunately, even under normal use, the seal will eventually wear and require
replacement.
A small puddle underneath the unit is a sign of rotary seal wear, and if investigation
confirms the pump as the source, the seal should be replaced as soon as practical. The
water slinger is intended to provide temporary protection against this, but a continued
and substantial leak will ruin the motor bearing and cause further damage.
After the unit has been in service for a period of years where abrasive conditions are
present, you may find that the pump bracket (the top half of the pump casting), can be
eroded away in the area around the seat of the rotary seal. This area should provide a
straight, smooth bearing surface for the cup seal. Should your casting show signs of
erosion in this area, the casting needs to be replaced. The replacement cost of the
casting is very modest compared to the down time and maintenance cost for frequently
replacing the seal.
Under some conditions, the pump may not start. After turning off the power supply,
check the motor shaft to be certain it is free to turn. By removing the drip cover on top
of the motor, you’ll have access to the end of the shaft. It has been slotted to make it
easy to turn with a screwdriver. If the shaft is free to turn, next check that the motor
overloads are set, check for blown fuses, and finally check the power supply on each
leg to the motor. A qualified electrician should check the motor and its circuit.
Important!
If the pump motor wiring is disconnected for removal from the unit,
make sure that you check the actual rotation direction
when the motor is rewired to the unit.
A phase sensor does not always indicate proper rotation
if motor wire leads are reversed at installation.
Consult the elementary wiring diagram for more information.