Gardner Denver ELECTRA-SAVER II Service Manual page 11

only, as standard equipment The enclosure reduces the
normal operating sound of the unit to 90 DBA or below
in free field conditions
AIR-COOLED OIL COOLER MODULE — The air-
cooled oil cooler is a separate module and may be mounted
remote to the compressor unit
Ventilation — The oil cooler requires adequate cooling air
flow. Proper ventilation MUST be provided with hot air
exhausted away from the cooler take care that hot air is
not recirculated from the exhaust to the inlet side of the
cooler. Cooling air flow direction is from the motor side
through the grille side of the oil cooler. Do not obstruct
the air flow to or from the cooler. Allow two (2) feet
clearance on all sides of the cooler module See Figure 2-2
for cooling air flow requirements
Low Oil Pressure Protection — The standard factory
installed low oil pressure shutdown switch in the control
box will prevent start-up or shut the unit down if oil pres
sure is not established or maintained due to malfunction
in the oil cooler system
Oil Cooler — The oil cooler module can be mounted in
any of several remote locations close coupled but not
joined to the compressor unit horizontal remote, located
on the same level as the compressor unit but some dis
tance away or overhead remote located above level of the
compressor unit as on a roof.
~WARNING
The low demand mode switch CANNOT be used with
remote overhead oil cooler These units require special
wiring diagram — check with factory.
All piping and wiring between the compressor unit and the
remote oil cooler is to be supplied by the user.
THE
DESIGN OF THE REMOTE OIL COOLER MODULE
SYSTEM MUST BE APPROVED BY THE FACTORY
BEFORE INSTALLATION. The design information to be
submitted for approval includes
1.
Location of oil cooler module — inside or outdoors
2. Range of operating ambient temperatures at the oil
cooler location
3. Elevation of the oil cooler above the compressor unit
4. Pipe type and size(s) to be used to connect oil cooler
and compressor unit Minimum pipe size is 2" IPS
5. Horizontal and vertical lengths of the pipe run If
more than one pipe size is used list length of each
size and total length.
6. Number and size of elbows tee% unions reducers
and valves to be used in the pipe run
7.
A dimensioned sketch of the proposed piping system
showing location of the compressor unit oil cooler
and pipe fittings of 3 through 6 above
All remote piping should be of adequate size to insure the
minimum pressure loss Design point4 above lists the pipe
size at the compressor unit oil inlet and outlet connections
and is the minimum pipe size to be used Long runs of pipe
and the use of valves and fittings require larger than the
minimum pipe sizes in the system to keep the pressure
loss low. All pipe and fittings used in a remote oil cooler
system should be galvanized or treated internally to pre
vent rust and all valves are to be of a nonferrous con
struction to prevent corrosion and fouling
The remote cooler should be placed so that the fan air flow
through the cooler (air flow is from motor side through
core) and the prevailing winds are in the same direction
A baffle should be provided on the exhaust side of the
cooler for protection against occasional wind shifts
When the oil cooler is mounted above the compressor unit
a check valve is to be mounted on the compressor unit in
the line to the oil cooler see Figure 2-5. A pneumatic pilot-
operated normal-closed valve is to be mounted at the
oil filter inlet on the compressor unit line from the oil
cooler see Figure 2-5. The check valve permits oil flow to
the oil cooler during operation, but prevents return oil
flow from the cooler when the unit is shut down The pilot
valve is held open by air pressure from the unit oil reservoir
during operation and closes under spring load when the
unit is shut down to prevent return oil flow from the oil
cooler.
An oil filler stand pipe and plug must be located in the
piping on the oil cooler module for ease of filling of a
remote oil cooler see Figure 2-5.
INSTALLATION FOR COLD WEATHER OPERATION
— It is recommended that whenever possible the unit be
installed inside a shelter that will be heated to temperatures
above freezing (32" F., 0° C.). This will eliminate many of
the problems associated with operating the units outside
in cold climates where freezing rain, drifting snow, freezing
condensate and bitter cold temperatures are encountered
When an outside installation must be made the precau-
tions required will depend on how severe the environment
will get The following are general guidelines for outside
installations
Cold Weather (Down To –10° F.)
1.
2.
3.
4.
5.
6.
13-9-630
Section 2
Be sure all control Iines drains and traps are heated
to avoid freezing of condensate Heat tape with ther-
mostat control is generally satisfactory for this pur-
pose. This is not a factory option but can be obtained
at various local plumbing or hardware outlets
If an air-cooled aftercooler is to be used provisions to
bypass the aftercooler should be made Since cold air
contains very little moisture successful operation can
be achieved without the aftercooler. Successful
operation down to +15° F. can be accomplished by
reversing fan flow, but cooler bypass should still be
provided should it be required
Provide at least some simple shelter (Plywood wind
break etc) to protect against drifting snow.
Use only
Gardner- Denver "GD800
Lubricating
Coolant'.
Monitor unit carefully during start-up and operation
to be sure it is functioning normally.
When the coolers are mounted horizontally use
weather protected enclosure for the unit
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