Satellite Slide Tank - Manual (Page 20)

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there is less pressure at hand to load your
tank. Table 3.4 lists the percentage loss of
attainable vacuum for every 1000-foot rise
in elevation over sea level.
While it is necessary to create enough
vacuum to handle pumping height, product
weight, and hose friction, it is important not
to overstress the pump. Pay close attention
to your pump if it is necessary to operate at
a high in./Hg vacuum level. Air- cooled
pumps are especially vulnerable to
overheating when being operated for
extended periods at high vacuum levels.
Liquid cooled pumps can handle this type
of operation much more readily.
In addition, operation at high in./Hg levels
can also result in moisture condensation in
the pump. As vacuum increases, water
begins to evaporate from the surface of the
liquid in the tank. Anytime that vacuum
pump operation exceeds 15"Hg, water
vapor can begin to show up in the air
circulating in the vacuum system.
While most of this moisture collects in the
oil catch muffler, some of it will also
accumulate inside the pump. In order to
prevent problems connected with water
collecting in your vacuum pump, dry it out
anytime that you notice that water has
collected in the oil catch muffler.
Table 3.4 Vacuum vs Elevation
Attainable Percentage of
Elevation Maximum loss per 1,000
Vacuum Level feet elevation
0 29.921 ----
1,000 28.85 3.6%
2,000 27.82 7.0%
3,000 26.82 10.4%
4,000 25.84 13.6%
5,000 24.89 16.8%
6,000 23.98 19.9%
7,000 23.06 22.9%
8,000 22.20 25.7%
9,000 21.38 28.5%
Use the following procedure to dry the
pump out:
• Unload the tank
• Open a load or dump valve (to keep from
building vacuum)
• Run the pump in vacuum mode for two
to five minutes
Water that is allowed to remain in your
vacuum pump can diminish performance
and cause serious damage. When water is
present inside the pump, sludge forms.
This can restrict the vanes from moving
freely inside the rotor slots, reducing the
efficiency of your pump. In addition, water
inside your vacuum pump can freeze
during cold weather operation. Attempting
to operate your pump if it is frozen inside
with ice will damage it.
`
NOTICE DO NOT run your vacuum
pump above the pump manufacturer’s
maximum continuous vacuum rating.
Exceeding the maximum vacuum rating
could cause damage to the pump and/or
tank.
„
IMPORTANT: After operating your
pump at high in./Hg vacuum levels, dry the
pump interior out using the procedure
outlined above. Water in your vacuum
pump can cause sludge formation and
freeze up in cold weather.
Unloading
You have two options when unloading the
tank on your slide-in unit, gravity dumping
or pressure dumping. Either method will
effectively empty the tank, however
pressure dumping increases discharge
flow rate.
Begin the unloading procedure by placing
the vacuum pump control handle into
neutral to relieve any vacuum in the
system, then use one of the following
procedures.
For gravity dumping, use the following