Page 114 - HVAC Pump Handbook

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Physical Description of HVAC Pumps

Physical Description of HVAC Pumps 111

The advantage of this configuration is the fact that the motor and
pump cannot be misaligned with each other. Many designers prefer
this pump over the flexibly coupled single-suction pump because of
this. Another advantage of this pump is its physical space require-
ments, which are less than those required by the flexibly coupled
single-suction pump. As indicated previously, the motor is special
because of the end bell mounting and the shaft extension and is not
stocked as readily as the standard motor.
2. Flexibly coupled (Fig. 5.2b). This pump is mounted on a base and
connected through a coupling to a standard motor. It can be equipped
with a spacer-type coupling that allows removal of the pump bracket
and impeller without moving the motor or its electrical connections.
This arrangement requires more equipment room space and must
be aligned carefully after the pump base is set in place. The flexible
coupling always must have a coupling guard in place before the pump
is operated. The principal advantage of this pump is the fact that it
uses a standard motor. In large motor sizes, it is less expensive than
the close-coupled pump. The pump base must be grouted to maintain
alignment of pump and motor.
3. Vertical mount (Fig. 5.3). The vertically mounted single-suction
pump is a close-coupled pump mounted on a pedestal-type long-sweep
elbow that provides the suction connection as well as the support for
the pump and motor. This pump, like the in-line pump, can save
equipment room floor space. A unique advantage of this pump is its
ability to rotate the discharge to accommodate the discharge piping.
4. In-line (Fig. 5.4). This configuration is so named because the
pump can be inserted directly in a pipeline. The suction and discharge
connections are in the same line, so there is no need for offsets or
elbows in the connecting piping.

Figure 5.3 Vertically mounted,
end-suction pump.

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