
When Installing Interceptor Inside
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
Fernco or similar rubber
flow restriction end cap
SPECIAL PRECAUTIONS
For Schier Grease Interceptor Installations - Failure to follow this guidance voids your warranty
High Water Table Installations
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.
Fully Support Base of Unit
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
Installation Instructions
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.
Hydrostatic Slabs
(or Pressure Slabs)
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.
Support Inlet and Outlet Piping
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.
High Temperature Kitchen Water
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).
cold water supply line
high temperature euent ( > 150º F)
approved backflow prevention assembly
DTV (drain water tempering valve)
directly connected indirectly connected
pipe supports
InterceptorInterceptor
concrete slab subject to hydrostatic pressure
watertight
concrete
vault
InterceptorInterceptor
InterceptorInterceptor
concrete floor
suspended installation
InterceptorInterceptor
Interceptor
Interceptor
max water table height for
direct burial
deadman anchor
nylon strap
turnbuckle
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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
AGS2
Above Grade Installation Support
(for Model GB-500 Only)
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
DO NOT
COMPACT
BACKFILL
DO NOT AIR TEST UNIT OR RISER SYSTEM!
Schier | GB-500-500HF Installation Guide
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