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Operation

Installation:
Rigging 4
Loading
Media
4
Piping
..
5
Electric Actuator Requirements
Wiring
..
6
Electrical
Requirements
6
Operation and Maintenance
Initial
and
Seasonal..
7
Start-
up
..
7
After First Hour of
Operation
8
Operation 8
Cold
Weather
Operation.
8
Seasonal
Shutdown..
9
Maintenance Procedures:
Pump Pre-
Strainer
9
Pump.. 9
Backwashing
.
9,10
Water
Treatment

11
Factory Authorized
Parts
11
SAFETY
PRECAUTIONS..
Warranty
..
12
Operation & Maintenance
Schedule
13
Tables
.
14 ~ 15 IMF Series Filter System
Operating & Maintenance Manual
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GENERAL DESCRIPTION
PEP IMF series high efficiency filters are permanent media type units specifically designed to
remove suspended particulates down to 0.45 micron from industrial and process water. IMF filters
are suitable for both side-stream and in-line applications on pressurized systems. The standard
pressure rating for IMF filter systems is 150 psig (1,050kPa). The filter vessel is constructed of
304 stainless steel to ASME Section VIII, Division I standards. Higher pressure ratings are
available. The filter vessel internals are also constructed of 304 stainless steel. The filter vessel has
a conical bottom with an annular ring under drain that is flush with the cone bottom. Because the
under drain is flush with the filter vessel bottom, this unique design eliminates stagnant water below
the under drain.
Filter Operation
Unfiltered system water is pumped to the IMF filter tangential inlet. Water enters the filter vessel
in a swirling motion that separates the larger and heavier particles from the liquid and keeps them
to the media bed perimeter. Water then flows through the media bed and suspended particles are
trapped within the filter media. The resulting filtered water passes from the vessel through the radial
bed fluidizers and annular ring under drain at the bottom of the filter and the filtered is returned to
the system.
When trapped particles cause the pressure differential across the media bed to reach a pre-
determined pressure of approximately 16 psig, the filter valves automatically reposition and the
media is fluidized in reverse flow. The accumulated particulate exits the filter vessel via the
tangential inlet and flows to a suitable drain. After which, the valves automatically reposition and
filtration continues. Depending on backwash flow rate, the filter may backwash anywhere from 90
seconds to three minutes (field selectable).
Installation
Unpacking
Immediately upon receipt, the PEP IMF filter should be checked thoroughly to ensure that all
required items have been received and the filter equipment is free from transportation damage
prior to signing the bill of lading. The filter serial number is located on a label affixed to the top
inside of the control panel enclosure. Check the serial number on the label with the
invoice/packing list to assure they match.
Rigging
The PEP IMF units should be lifted with a forklift or overhead crane.
Note
: The lifting lugs located on either side of the filter vessel should be used when lifting the
filter vessel only. The vessel must be empty of all water and media. If these units are lifted with
an overhead crane, the filter vessel must be removed from the base and lifted separately. Lifting
straps must be located below the base and should not come in contact with filter components
(pump, face piping, control panel, etc.).
All PEP water filters should be anchored to the floor by means of anchor bolts. The IMF base IMF Series Filter System
Operating & Maintenance Manual
PEP Filters 322 Rolling Hill Road Mooresville, NC 28117 800-243-4583

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has holes suitable for 1/2" anchor bolts.
After the unit has been installed, locate the pressure gauge and air relief valve (shipped inside the
control panel) and install them on the top of the filter vessel.
Media Loading
Note: Never load gravel into a dry filter vessel.
First, fill the vessel with water
approximately one foot above the radial arm fluidizers. Three different types of sand media are
supplied with the filter. Media is loaded into the vessel in the quantities provided, starting with
the largest size (gravel) and ending with the finest (smallest). Refer to Table 6 for the required
types and quantities of media.
Next, load the filter media (sand, gravel, etc.) into the filter. Refer to the following section for a
description on how to load the media into the filter vessel and the appropriate quantity of media
necessary for each filter size.
The specially manufactured spherical silica sand media used in PEP InterSeptor media filters is
designed to remove suspended solids 0.45 micron and larger, over 90% by volume. The media
will ship to the job site in _ cubic ft. drums (50 lbs/23 kg) or 1 cubic ft. bags (100 lbs/46 kg) for
ease of handling during the media loading process.
Actual quantities may vary slightly with vessel pressure ratings. Correct quantities will be noted
on the shipping and inspection records for each system. Always check integrity of filter
internals before loading media.
Piping
The PEP IMF filter should be installed as follows:
1.

Connect a feed water line from the system sump or piping to the connection labeled
"Inlet" on the pump. If the inlet connection is located above the operating water level of
the system sump, install a foot/check valve to prevent pump suction loss.
2.

Connect the return line from the connection labeled "Outlet" to the system sump or
piping.
3.

A service valve should be installed on the inlet, outlet, and city water line (if city water is
used for backwash) to allow filter servicing. For units using a backwash source other
than the system matched pump, refer to the Backwash Flow Rate vs Time graph to
determine the required backwash flow rate. Connect this line to the fitting labeled "City
Water". The maximum city water backwash supply pressure on the IMF filters should
never exceed the pressure rating of the filter vessel. If public or municipal water is used
for backwash, a reduced pressure back-flow prevention or check valve is required in the
line (refer to local codes).
Connect a backwash waste line to the connection labeled "Waste". This line carries the IMF Series Filter System
Operating & Maintenance Manual
PEP Filters 322 Rolling Hill Road Mooresville, NC 28117 800-243-4583

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backwash wastewater to the drain. Do not put a valve in the backwash line and never reduce
the backwash line size.
Note
: If the drain is not large enough to handle the backwash flow rate, it may be necessary
to use a backwash holding tank to collect the wastewater, and regulate the flow from the
holding tank to drain.
4.

All interconnecting piping, fittings, valves, or other accessories connected to the filter
system (whether supplied by PEP or others) must be independently supported to
eliminate stress on piping.
Check with local, county, or other government authorities to ensure compliance with applicable
government or industry codes.
Note
: The _ (20 mm) drain plug on IMF units is located on the tank bottom outlet.
Actuator Requirements
PEP IMF filters utilize electric actuators to control the valve action between the filtration and
backwash cycles. The electric actuator is designed for 110 VAC control.
Wiring
IMF filters are supplied with a pump and automatic backwash controls and the following system
components: NEMA 4X (IP32) control enclosure containing an on/off disconnect switch, motor
overload protection, transformer to provide 110 VAC control voltage, adjustable backwash timer,
24 hour time clock, pressure differential switch to initiate backwash, valve actuator to reposition
valves for backwash, and push button for manual backwash initiation. Units are provided with
460 VAC, 3 close-coupled pump/motor assembly.
IFM filter units configured for using city water backwash are provided with a magnetic motor
starter.
The following recommendations conform to the 1993 national electric code. Check with local,
county, or other government authorities for prescribed requirements.
Note
: Refer to the pump/motor nameplate for horsepower and current draw.
Single and Three Phase Automatic Units
Install a separate power supply line with circuit breaker protection between the closest branch
distribution panel and the control box. The full load current for standard single and three phase
units is listed in Tables 4 & 5. The control box contents are pre-wired and include a service
disconnect switch, thermal overload/short circuit protection, and a transformer to convert the
power supply to single phase 110 VAC for controls (for pump motor voltages other than 110 IMF Series Filter System
Operating & Maintenance Manual
PEP Filters 322 Rolling Hill Road Mooresville, NC 28117 800-243-4583

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VAC). Wire the power supply lines to the disconnect switch. All incoming power supply lines
must connect to the door interlock disconnect. IMF Series Filter System
Operating & Maintenance Manual
PEP Filters 322 Rolling Hill Road Mooresville, NC 28117 800-243-4583

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Operation And Maintenanc