Schier GB-50 User manual

Contents
Special Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
General Installation Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Below Grade Installation Instructions . . . . . . . . . . . . . . . . . . . . . . 5
Anchor Kit Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Field Cut Riser Installation Guidelines . . . . . . . . . . . . . . . . . . . . . . 6
Application Specific Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Document #: 057-0850-04
Find these instructions online at: schierproducts.com/gb-50
INSTALLATION GUIDE
GB-50 50 GPM Grease Interceptor for Indoor/Outdoor Use

Page 2 of 7
GB-50 Installation Guide
When Installing Interceptor Inside
Fernco or similar
rubber flow
restriction end cap
SPECIAL PRECAUTIONS
Installation Instructions
Hydrostatic Slabs (or Pressure Slabs)
High Temperature Kitchen Water
concrete slab subject to hydrostatic pressure
watertight
concrete
vault
Do not install this unit in any manner
except as described in these instructions.
Doing so may result in property damage, personal injury or death.
installation
instructions
DO NOT AIR TEST UNIT OR RISER SYSTEM!
For Schier Grease Interceptor Installations - Failure to follow this guidance
voids your warranty
cold water supply line
high temperature
effluent ( > 150º F)
approved backflow
prevention assembly
DTV (drain water
tempering valve)
directly connected indirectly connected
If water is entering the interceptor at excessive temperature (over
150º F), a drain water tempering valve (DTV) and approved backflow
prevention assembly must be installed. Most state and local
plumbing codes prohibit water above 150º F being discharged into
the sanitary sewer. Water above 150º F will weaken or deform PVC
Schedule 40 pipe, poly drainage fixtures like interceptors and erode
the coating of cast iron (leading to eventual failure).
Installation instructions and additional
components are included with the
interceptor. Read all instructions prior
to installation. This interceptor is
intended to be installed by a licensed
plumber in conformance with all
local codes.
If your dishwashing sink(s)
discharges into a floor
drain/sink (drain), you
must regulate the flow into
the drain to avoid an
overflow of water onto the
kitchen floor. This can be
done by installing a valve
or flow restriction cap on
the sink piping that
discharges into the drain.
See drawing for guidance. For detailed guidance on indirect
connections, go to:
webtools.schierproducts.com/Technical_Data/Indirect_Connections.pdf
When installed under a
hydrostatic slab (slab
designed to withstand
upward lift, usually
caused by hydrostatic
pressure) interceptor
must be enclosed in a
watertight concrete vault.
Interceptor
Interceptor
Interceptor
Interceptor
Interceptor
Interceptor
Interceptor
Interceptor
Interceptor

SPECIAL PRECAUTIONS
AGS2
The wet weight of the interceptor combined
with high temperature kitchen water
creates the potential for tank deformation
when installed above grade. Model GB-500
installed above grade must be installed
with Above Grade Support Kit model AGS2
to maintain structural integrity
Above Grade Installation Support
(for Model GB-500 Only)
Install unit on solid, level surface in
contact with the entire footprint of
unit base; for suspended
installations design trapeze to
support the wet weight of the unit.
Do not partially support unit or
suspend unit using metal
U-channel to create a trapeze.
Fully Support Base of Unit
For above grade installations ensure
heavy inlet and outlet piping (such as
cast iron or long runs) is properly
supported or suspended during the
entire installation process to prevent
connection failure or damage to
bulkhead fittings.
Support Inlet and Outlet Piping
pipe supports
suspended installation
DO NOT
COMPACT
BACKFILL
Page 3 of 7
GB-50 Installation Guide
For Schier Grease Interceptor Installations - Failure to follow this guidance
voids your warranty
Interceptors and risers are not
designed to withstand water table
height in excess of the top of the
unit when buried (see figure). If it is
possible for this to occur, install the
interceptor and risers in a
water-tight concrete vault or
backfill with concrete or flowable
fill (wet concrete and flowable
backfill should be poured in
stages to avoid crushing the
interceptor). At risk areas include
but are not limited to tidal surge
areas, floodplains and areas that receive storm water. Great Basin™
models that are direct buried in high water table scenarios must be
installed with an anchor kit. Models GB-50, GB-75, and GB-250 use model
AK1 anchor kit. Model GB-500 uses model AK2 anchor kit for use with
deadmen anchors.
max water table height
for direct burial
model AK1
anchor kit
High Water Table Installations
Interceptor
Interceptor
Interceptor
concrete floor
Interceptor
Interceptor
Interceptor

LEAK/SEAL TESTING
Cap/plug all base unit plumbing connections and remove covers.
For base unit testing,fill with water to just above the highest
connection. For riser system testing (if required) fill with water to
finished grade level. CAUTION: Risers must be supported before
filling with water to prevent tipping. Inspect unit, connections and
all gaskets and clamps (if applicable) for leaks. Check water level at
specific time intervals per local code.
GENERAL INSTALLATION INSTRUCTIONS
Schier grease interceptors are manufactured with an internal flow
control system. They do not require an external flow control
system or air intake vent. Schier grease interceptors are not to be
installed in any other manner except as shown. Consult local
codes for separate trapping requirements, cleanout locations and
additional installation instructions.
1. Flow control is not pre-installed on this unit. If Dimension "A" in
Figure A is more than 13 feet, or when the unit is installed in a
high flow/increased head pressure condition (with a flow rate
above 50 GPM), slide flow control cartridge into top of inlet
diffuser and rotate clockwise until cartridge drops onto flow
control retainer pins. Continue rotating clockwise until pins are
fully seated in the cartridge receiver slots.
OPTIONAL: For easy flow control removal in deep burial
installations, 1-1/2" PVC SCH. 40 pipe may used as an extension
handle. Before risers have been installed, cut pipe to length and
attach to top of flow control cartridge using PVC primer/cement.
2. Set unit on level solid surface as close as possible to fixtures
being served.
3. Set Up Outlet Diffuser. Interceptor is shipped with outlet diffuser
in the straight-through configuration (outlet B). For optional side
outlet configurations, first remove the outlet diffuser by loosening
its retaining nut. Next, remove the outlet diffuser foot by
loosening its retaining nut. Reposition the foot so that it points
toward the back wall of the unit and replace, hand tightening its
retaining nut. Finally, place the reconfigured outlet diffuser into
the chosen side outlet fitting and hand tighten its retaining nut.
4. Cap all unused connection points with 4" cleanout plugs using
pipe thread sealant or tape approved for use with plastics.
5. Choose inlet and outlet fittings based on pipe size. Connect inlet
and outlet drainage lines to unit. Connect piping using pipe
thread sealant or tape approved for use with plastics.
Mechanically couple pipes to unit. Do not solvent weld. Ensure
all upstream fixtures are trapped. Vent per local code.
6. For unit with cast iron covers, remove retainer clips prior to burial.
NOTE: Do not install below a hydrostatic slab without enclosing
interceptor in a watertight concrete vault.
Outlet Diffuser
Retaining Nut
Diffuser Foot
Retaining Nut
Diffuser Foot (must face this
direction in all configurations)
Outlet A
(Optional) Outlet B (Standard) Outlet C (Optional)
INSTALLATION
Page 4 of 7
GB-50 Installation Guide
Figure A
FLOW CONTROL INSTALLATION
OUTLET DIFFUSER CONFIGURATIONS
Flow Control
Cartridge
Optional 1-1/2" PVC
Extension Handle
Flow Control
Retainer Pin
Cartridge
Receiver Slot

BELOW GRADE INSTALLATION INSTRUCTIONS
EXCAVATION
1. Surrounding soil must be undisturbed soil or well compacted
engineering fill.
2. Width and length of excavation shall be a minimum of 12"
greater than the tank on all sides and depth shall be 6" deeper
than tank bottom.
3. Set the tank level on a 6" deep layer of well-packed crushed
aggregate material and connect waste piping per General
Installation Instructions.
BACKFILL
1. Preparation of sub grade per geotech recommendations.
2. Stabilize and compact sub grade to 95% proctor.
3. Fill unit with water before backfilling to stabilize unit and prevent
float-out during backfilling. Secure covers and risers (if necessary)
to the unit.
4. Backfill evenly around tank using crushed aggregate (approxi-
mately 3/4" size rock or sand, with no fines), or flowable fill. Do not
compact backfill around unit.
FINISHED CONCRETE SLAB
Slab must extend 18" minimum outside the footprint of the unit.
Pedestrian traffic or greenspace areas: 4" Thick reinforced
concrete slab required.
Vehicular traffic areas: Minimum 8" Thick concrete slab with rebar
required. Thickness of concrete around cover to be determined by
specifying engineer. If traffic loading is required the concrete slab
dimensions shown are for guideline purposes only. Concrete to be 28
day compressive strength to 4,000 PSI. Use NO. 4 rebar (ø 1/2") grade
60 steel per ASTM A615: connected with tie wire. Rebar to be 2-1/2" from
edge of concrete and spaced in a 12" grid with 4" spacing around
access openings.
ANCHOR KIT INSTALLATION
Stainless steel anchor kit is recommended for installation in high
water table conditions to prevent float out. Necessity to be deter-
mined by specifying engineer. Hold down force achieved by backfill
weight acting on Anchor Plate.
Slide Anchor Hook over tie down point on end wall and bolt to
Anchor Strap. Bolt Anchor Strap to Anchor Plate using provided
stainless steel hardware. If required, Anchor Plate may be bolted to
concrete slab using provided holes.
Optional anchor kit
Native soil
Backfill
Well packed base
Concrete slab
Finished grade
Adapter
Riser
EXCAVATION AND BACKFILL DETAIL
Finished grade 4"
8" (Vehicular trac)
TOP VIEW
ELEVATION VIEW
18" min
45º
18" min
Rebar
Rebar
Concrete Slab
4" Thick for pedestrian
8" Thick for vehicular
Recommended 2-Way
cleanout tee to grade
(by others)
Optional anchor kit
Riser to Grade
SIDE VIEW DETAIL
CONCRETE SLAB DETAIL
18"
min 18" min
Anchor hook
Anchor strap
Anchor plate
ANCHOR KIT INSTALLATION DETAIL
Finished grade
INSTALLATION
Page 5 of 7
GB-50 Installation Guide

FIELD CUT RISER (24 SERIES)
INSTALLATION GUIDELINES
Tools needed: 7/16" Nut driver tool/bit (included), marker
(included), tape measure and drill with 1/2" chuck. Jigsaw,
circular saw or reciprocating saw will be needed if risers need
to be cut.
NOTE: To remove a component or adjust its position, the
Upper Band Clamp needs to be loosened or removed using
nut driver bit. The Lower Band Clamp is factory set and
should not be removed. For proper fastening ensure clamps
are tightened to 5 - 8 ft lbs. of torque (same as a rubber
no-hub coupling) prior to installation.
Riser Assembly Instructions/Steps
1. Set unit so the pipe connections line up with job site
piping and measure riser height needed from top of cover
to finished grade. See Table 1 to select risers needed.
2. Remove covers from adapters. Remove adapters from
main unit. On a level surface, pre-assemble the risers and
adapters, adjusting the components upwards or
downwards to achieve the riser height needed. Make sure
to maintain minimum and maximum insertion depths as
shown in Figure 2. If components are too long, make a
circular line around the sidewall with marker and cut with
a power saw. The lowest cut line on the riser assembly will
be 6" beyond the riser height needed to allow for ideal
insertion depth (See Figure 1). An alignment mark should
be drawn 2" beyond the riser height needed which will
align with the top of the base unit gasket. DO NOT cut the
alignment mark. The Adapters and risers should sit level
with each other. Tighten upper clamps to keep
riser/adapter assembly from shifting. Make alignment
marks on the sidewalls at the top of all riser gaskets to aid
final assembly.
3. IMPORTANT: Before the next step, make sure both
diffusers are installed inside the main unit at the
appropriate locations. Check if there needs to be any flow
contropl adjustment at the inlet diffuser (see general
installation instructions).
4. Take apart riser assembly and clean all sidewalls and
insides of gaskets to remove dust/debris. Install
components into the main units starting from the lowest
riser and work your way up to finished grade. Ensure that
riser will not interfere with diffuser, allow min. 1" clearance.
Maintain minimum and maximum insertion depths for all
components (see Figure 2). Tighten Upper Clamps to specified torque after correctly positioning components. Riser assembly may need to
be supported during backfill.
5. If tilting of the adapter is required to be flush with grade, do so AFTER all clamps have been tightened with riser(s)/adapter in a vertical and
level position. Tilting is done using gasket flexibility. Tilting before tightening clamps may ruin a perfect gasket seal. Schier recommends
tilting only the adapter versus the entire riser assembly to make sure your riser height and proper tank access is maintained.
6. If riser height conditions change after completing above steps, there may be room for adjustment. As long as minimum and maximum
insertion depths are maintained (see Figure 2), the adapters/risers can be adjusted/cut as many times as necessary.When riser system
installation is complete, see Leak/Seal Testing procedure if required (pg 3 of 6).
Table 1
Riser Height Needed Risers Required
0 - 3-1/2" None (use adapter)
5" - 23" SR24
>23" - 38" LR24
Riser
Height
Needed
Adapter
Riser
Cut Line
Alignment Mark
6"
2"
4"
LR24
Long Riser
Adapter
SR24
Short Riser
Cover
Gasket
Field Cut Riser
Components
Figure 1 - Riser Measurements
Figure 2 - Insertion Depths
2-1/2" Minimum
Insertion Depth
4" Maximum Insertion Depth
(into GB unit only)
Adapter (shown)
or Riser
Upper Band Clamp
(field adjustable)
Lower Band Clamp
(factory set - do not
adjust or remove)
GB Unit (shown)
or Riser
INSTALLATION
Page 6 of 7
GB-50 Installation Guide

APPLICATION SPECIFIC DETAILS
Recessed and Suspended
Additional Venting for Floor-Below Installations
Installation with Sampling Port SV24-L4
Inside a Corroded Concrete Unit
Serving an Apartment Complex
Vent must
terminate above
the top rim of
the sink
Must be fully
supported
Vent
Stack
Kitchen
Floor
Add this vent if unit is
installed one or more
floors below the
fixtures being served
*Venting examples shown are typical,
check local code for requirements
Pumpout port
kit (By Schier)
Basement Installation with Pumpout Port Kit
Cam Fitting for
pumper hook-up
(provided in kit)
Valve
(optional)
Piping (by others)
Page 7 of 7
GB-50 Installation Guide