GE Pegasus MHV GEEP-427-I Instuctions page 43

Air-to-Water Heat Exchanger
General
Totally-enclosed
contain an air-to-water heat exchanger in the top cover.
Shut-off water values should be installed in both the
water inlet and outlet pipes leading to and from the heat
exchanger. When installing the piping to the heat
exchanger, care must be taken to avoid pipe strains
which put a twisting force on the water box. If this
precaution in not followed, leaks at the gasket joints
between the water box and covers, or between the water
box and tube sheets, may occur. A flow meter should
always be provided in the water supply line with high
and low flow alarm contacts. In the event of an internal
leak in the heat exchanger, the top cover has drip baffles
connected to an external fitting for ducting water. A leak
detector switch (if originally ordered) with alarm
contacts is connected to the external fitting to operate an
alarm. Provisions are available for adding a switch, if not
originally ordered.
The water-flow rate, maximum inlet temperature,
and maximum water pressure drop are indicated on the
machine nameplate. Confirm that these values are met.
The flow of water through the heat exchanger should be
regulated by the outlet value to insure that the heat
exchanger operates full of water at all times.
GE Energy Motors GEEP-427-I
water-air cooled machines
GEEP-427-I Pegasus, Horizontal Induction Motor
Efficient operation of the heat exchanger requires
that no air be collected in the cooler tubes. To prevent
collection of air, a small pipe should be connected from
the air-vent-pipe coupling to the discharge piping of the
cooler, as well as any other point to vented. It is
recommended that a small flow of water be allowed to
pass continuously to vent of any entrained air from the
water supply.
Unless otherwise specified on the purchase order,
the heat exchanger supplied with this machine must use
clean water. If the cooling water contamination is
questionable, adequate filters should be provided to keep
maximum particle size less than 3/16 inch diameter.
Water quality considerations include salinity, acidity or
alkalinity, minerals in solution and presence of particles.
All of these must not be in concentrations which would
erode, crack, or corrode the tubes. If the machine is
located in
temperatures -- less than or equal to 0 C (32 F), provision
must be made to drain the cooler when the unit is shut
down.
After the heat exchanger has been filled with
water, and before the machine is energized, all cooler
gaskets and cooler joints should be developed during
shipment or installation of the unit.
Copyright 2009, The General Electric Company, USA 43
TEWAC, Sleeve Bearing
an environment subject to freezing