Schier GB3 User manual

Part #: 057-1270-04
Find these instructions online at: schierproducts.com/pages/gb3
INSTALLATION GUIDE
Model #GB3 50/75 GPM Grease Interceptor
For Indoor Use
Contents
Special Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Geing to Know the GB3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
On the Floor Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6
Buried Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9
Installation Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Page 2 of 10
GB3 Installation Guide
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 above for
guidance. For detailed guidance on indirect connections, go to:
hp://webtools.schierproducts.com/Technical_Data/Indirect_Connections.pdf
SPECIAL PRECAUTIONS
For All Schier Grease Interceptor Installations - Failure to follow this guidance voids your warranty
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.
Fernco or similar
rubber flow
restriction end cap
installation
instructions
inside
Interceptor
Interceptor
Interceptor
concrete floor
suspended installation
Interceptor
Interceptor
Interceptor
Flush-to-Grade Burials
Flush-to-Grade buried installations
(without a riser) are not recommended
for heavy foot traffic areas without the
use of an internal support system
(sold additionally).
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 fiings.
pipe supports
Interceptor
Interceptor
Interceptor
High Temperature Kitchen Water
If water is entering the interceptor at excessive temperature (over 140º F), a
drain water tempering valve (DTV) and approved backflow prevention assembly
must be installed. Most state and local plumbing codes prohibit water above
140º F being discharged into the sanitary sewer. Water above 140º 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 effluent ( > 140º F)
approved backflow prevention assembly
DTV (drain water tempering valve)
directly connected indirectly connected
Interceptor
Interceptor
Interceptor
Interceptor
Interceptor
Interceptor

GETTING TO KNOW THE GB3
Page 3 of 10
GB3 Installation Guide
1. Cover
2. Air Relief/Visual Access
3. Inlet Diffuser (Top)
4. 4" Cleanout Plug
5. Optional Side Outlet 4" FPT
6. Connection Fiing Gasket
7. Bulkhead Retaining Nut
8. Standard Installation Flow Control Plate (Red)
9. Flow Control Plate (>5' below kitchen only)
10. 3" Plain End Fiing
11. 4" Plain End Fiing
12. Inlet 4" FPT Connection
13. Saddle Adapter Retaining Nut
14. Saddle Adapter
15. Inlet Diffuser (Foot)
16. Cover Bolts (x4)
17. Cover Gasket
18. Outlet 4" FPT Connection
19. Outlet Diffuser (Top)
20. Outlet Diffuser (Foot)
2
3
7
6
4
5
9
8
1
12
5
6
13
14
15
11
14
19
13
6
18
5
11
10
20
16
17
7
4
5
6
10

Page 4 of 10
GB3 Installation Guide
ODOR ALERT!
Do not install air
gap on outlet side
of interceptor.
ODOR ALERT!
Interceptor is not a sewer gas trap.
All upstream fixtures must be trapped
ON THE FLOOR INSTALLATION
Special Precautions
Read all instructions
before installation
Install in conformance
with all local codes
Install interceptor as close as
possible to fixtures being served
DO NOT AIR TEST UNIT OR RISER SYSTEM!
Doing so may result in property damage,
personal injury or death.
1 2 3
4
5
Provide at least 5-1/2" clearance
above unit for routine maintenance.
5-1/2" min.
5-1/2" min.
5-1/2" min.
6
2 Configure outlet diffuser and install cleanout plugs
2h
Remove diffuser
from saddle.
Side outlet
Straight-through
Remove
saddle adapter.
Remove set screws
from foot, remove foot.
2b 2c 2d2a
Install saddle adapter
on desired outlet.
2e
Install
cleanout
plugs into
unused outlet
connections using
pipe thread sealant or tape
approved for use with plastics.
2f
Seat diffuser firmly
into saddle.
2g
Choose outlet
location.
Rotate
diffuser
top toward
desired outlet,
while ensuring
foot is pointed
toward the back
wall of the unit.
Reaach
foot and set
screws.
Cap all
connection
points with
4" cleanout plugs using
pipe thread sealant or tape
approved for use with plastics.
Remove cover and fill with
water to just above the
highest connection. For
riser system testing (if required)
fill to finished grade level.
CAUTION: Support risers
before filling to prevent tipping. Inspect unit,
connections and gaskets for leaks. Check water
level at specific time intervals per local code.
1a 1b Leak?
Call customer
care at 913-951-3300
8a – 5p M – F CST
1 Test tank for water tightness

Page 5 of 10
GB3 Installation Guide
Depending on which flow rate is
desired, snap-in the "50 GPM" or
"75 GPM" white flow control plate
as shown on inlet saddle adapter.
3d
ON THE FLOOR INSTALLATION
3 Calibrate Flow Control
• If dimension "A" above is 5 feet or
less go to Step 4, Connect Piping.
• If dimension "A" above is greater
than 5 feet follow Steps below.
Figure 1
Remove inlet diffuser. Remove red flow control plate from
inlet diffuser and discard.
Remove inlet saddle adapter.
3a 3b 3c
Re-install saddle adapter, ensure
flow control plate opening is down
as shown.
Seat inlet diffuser firmly into
saddle adapter.
3e 3f
Note to Plumbing Inspector
This interceptor includes certified internal
flow control and does not require a
dedicated “Flow Control Vent” (air intake).
Interceptor
Interceptor
Interceptor
OR
OR
OR

Page 6 of 10
GB3 Installation Guide
ON THE FLOOR INSTALLATION
Choose inlet and outlet fiings (included)
based on pipe size.
4a
4 Connect Piping
5 Wet or Air Test Piping Per Local Code
Doing so may result in property damage, personal injury or death.
DO NOT AIR TEST UNIT OR RISER SYSTEM!
1
Leak? Call customer care at
913-951-3300
8a – 5p M – F CST
4b
Connect piping using pipe thread sealant or tape approved for use with
plastics. Ensure all upstream fixtures are trapped. Vent per local code.
4b2
4b3
vent per
local code
Next to Sink
5-1/2" min.
vent per local code
Under Sink
vent per
local code
Floor Below
4b1
OR
OR
4" FPT
4" FPT
4" FPT
3" PE
4" PE
4" PE
4" PE

BURIED INSTALLATION
Special Precautions
DO NOT AIR TEST UNIT
OR RISER SYSTEM!
Doing so may result in
property damage,
personal injury or death.
Read all
instructions
before installation
Install in
conformance
with all local codes
Install
interceptor
as close as
possible to
fixtures
being served
2 Risers (25") Max Max Water Level
Risers are not designed
to retain water
1 2 3 4 5
Page 7 of 10
GB3 Installation Guide
2 Configure outlet diffuser and install cleanout plugs
2h
Remove diffuser
from saddle.
Side outlet
Straight-through
Remove
saddle adapter.
Remove set screws
from foot, remove foot.
2b 2c 2d2a
Install saddle adapter
on desired outlet.
2e
Install
cleanout
plugs into
unused outlet
connections using
pipe thread sealant or tape
approved for use with plastics.
2f
Seat diffuser firmly
into saddle.
2g
Choose outlet
location.
Rotate
diffuser
top toward
desired outlet,
while ensuring
foot is pointed
toward the back
wall of the unit.
Reaach
foot and set
screws.
Cap all
connection
points with
4" cleanout plugs using
pipe thread sealant or tape
approved for use with plastics.
Remove cover and fill with
water to just above the
highest connection. For
riser system testing (if required)
fill to finished grade level.
CAUTION: Support risers
before filling to prevent tipping. Inspect unit,
connections and gaskets for leaks. Check water
level at specific time intervals per local code.
1a 1b Leak?
Call customer
care at 913-951-3300
8a – 5p M – F CST
1 Test tank for water tightness

BURIED INSTALLATION
Page 8 of 10
GB3 Installation Guide
Depending on which flow rate is
desired, snap-in the "50 GPM" or
"75 GPM" white flow control plate
as shown on inlet saddle adapter.
3d
Interceptor
Interceptor
Interceptor
Figure 1
• If dimension "A" above is 5 feet or
less go to Step 4, Connect Piping.
• If dimension "A" above is greater
than 5 feet follow Steps below.
3 Calibrate Flow Control
Note to Plumbing Inspector
This interceptor includes certified internal
flow control and does not require a
dedicated “Flow Control Vent” (air intake).
Remove inlet diffuser. Remove red flow control plate from
inlet diffuser and discard.
Remove inlet saddle adapter.
3a 3b 3c
Re-install saddle adapter, ensure
flow control plate opening is down
as shown.
Seat inlet diffuser firmly into
saddle adapter.
3e 3f

4" FPT
4" FPT
4" FPT
3" PE
4" PE
4" PE
4" PE
BURIED INSTALLATION
Page 9 of 10
GB3 Installation Guide
Set interceptor and
connect piping using
pipe thread sealant or
tape approved for use
with plastics, fill tank with
water so that it remains
in place during backfill.
Choose inlet
and outlet
fiings
(included)
based on
pipe size.
4c
Excavate hole 6" larger than interceptor on all sides. Add crushed aggregate (approximately 3/4" size rock or sand,
with no fines) to base of hole.
4a 4b
6" or more
6"
6"
6"
6a1
Below Grade with Riser (preferred): See instructions
included with FCR1 riser. Backfill evenly around tank using
crushed aggregate (approximately 3/4" size rock or sand,
with no fines), finish with a minimum 4" thick concrete pad.
Vent per local code.
6a2
4" min.
concrete pad
Backfill1,000 lb.
max load
Tile 4" min.
concrete pad
Backfill450 lb.
max load
Tile
Floor Sink Installation
Fernco or similar
rubber flow
restriction end cap
Interceptor
Interceptor
Interceptor
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.
4 Connect Piping
6 Backfill and Finished Grade
5 Wet or Air Test Piping Per Local Code
4c1
OR
OR
OR
Doing so may result in property damage, personal injury or death.
DO NOT AIR TEST UNIT OR RISER SYSTEM!
1
Leak? Call customer care at
913-951-3300
8a – 5p M – F CST
Flush-to-Grade Burials:
Not recommended for heavy foot traffic
areas without the use of an internal support system (sold
additionally). Contact Customer Care for more details.
WARNING!

Page 10 of 10
GB3 Installation Guide
INSTALLATION OPTIONS
This grease interceptor features a standard closed top inlet diffuser which may be modified to an
open top if any of the following conditions apply:
1. This interceptor is part of a series installation and is NOT the first interceptor in the series.
2. An open site drain / indirect connection located upstream is experiencing frequent backups.
3. Local code requires a visual inspection point for the inlet diffuser.
NOTE: Modifying the inlet diffuser to an open-top style eliminates the sewer gas seal and should only be
performed if sewer gas is trapped upstream of the unit.
1 Open Top Inlet Diffuser Modification
Remove inlet diffuser. Seat inlet diffuser firmly into
saddle adapter
1a 1c
Cut open the inlet diffuser top.
1b
Cut Line