Frequently Asked Backflow Questions LBS845 5 Fabqs
User Manual: LBS845-5
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Frequently Asked Questions
• What are the differences between the Model 830 and Model 845?
1. The DP gauge in the model 830 is permanently mounted in a sturdy double
walled case giving it maximum protection from drops and impacts at a weight
of 14 lbs. The model 845 is not permanently mounted in a case making it
more portable and light weight at about 3.5 lbs with the DP gauge more
exposed during testing.
2. The model 830 is available as a 5-valve test kit. The model 845 is available as
either a 5-valve (845-5), 3-valve (845-3) or 2-valve (845-2) test kit giving the
tester more choices.
3. The hoses for the model 830 are permanently attached to the test kit. The
hoses for the model 845 are removable.
4. The model 830 can be hung around pipes or supports with a ball chain while
the 845 can be hung or worn around the neck or shoulder with the supplied
strap.
5. Because of the portable design of the 845 it is easier to bleed and drain than
the model 830.
Bottom line – Training schools and municipalities that have multiple testers using
the same test kit prefer the 830 because of its protection in the case. Individual
testers buying a kit for their own personal use prefer the 845 because of its light
weight and portability.
• What are the similarities between the Model 830 and Model 845?
1. Both models come complete with adapter fittings for test cocks from 1/8” NPT
through ¾” NPT, in-line hose filters, soft seated needle valves, line pressure
gauge and laminated test procedures.
2. Both models carry an industry best 5-year limited warranty for material and
workmanship.
3. Both models are capable of performing all know test procedures including
those recommended by ASSE, AWWA, CSA, FCCC & HR-USC and NEWWA.
4. Both models will test all brands and types of backflow prevention assemblies
including Reduce Pressure Principle Assemblies (RPs), Double Check Valve
Assemblies (DCs), Pressure Vacuum Breakers (PVBs), Spill Resistant
Vacuum Breakers (SVBs), Reduced Pressure Principle Detector Assemblies
(RPDAs) and Double Check Detector Assemblies (DCDAs).
5. Both models can be serviced at any of our 20 regional service centers.
6. Both models are on the “Recognized Gages” list of FCCC & HR-USC and
CA-NV AWWA.
• What are the advantages of Quick Connect Test Cock Adapters?
1. No wrenching or pipe thread sealant is required for installation or removal
making them a big time saver because they are installed and removed by
hand.
2. Since they are installed by hand there is no chance of breaking a test cock
which can occur when wrench tightening a traditional NPT adapter.
3. Since they are removed by hand there is no chance of accidentally removing
the test cock rather than the adapter which can occur when removing a
traditional NPT adapter.
4. The 90° elbow-360° rotary swivel adapters PN 110705 or in the kit PN 110706
allow easy test kit connection to improperly installed backflow preventers or
backflow preventers installed in very tight spaces.
Bottom line – These accessories allow you to save time connecting and
removing your test kit to a backflow prevention assembly improving the efficiency
of testing.
• What are the advantages of the Professional Test Cock Cleaning Tool
PN 110694?
1. Safety. The plunger is blow-out protected and will not fly out or your hand like
a screw driver, weld rod or coat hanger potentially injuring you, your
associates or your customers.
2. The debris blocking the test cock can be diverted through the hose in a
controlled manner into a bucket or drain rather than spraying rusty water all
over the tester or customer’s property.
3. The plunger end is blunt and will not damage the internals of the backflow
preventer which could happen with a screw driver, weld rod or coat hanger.
• What is the purpose of the PN 830-0001 Bleed-off Compensating Tee and PN
830-0003 Vertical Tube Kit?
P.N. 830-0001 Compensating Tee Assembly and 830-0003 Vertical Tube Kit Assembly
Theory of Operation
The Mid-West Instrument Backflow Test Kit Accessories 830-0001 and 830-0003 are
designed for use with the USC field test procedures for double check valve assemblies,
pressure vacuum breaker assemblies and spill resistant pressure vacuum breakers per the
USC Manual of Cross-Connection Control.
The theory of operation is as follows:
Proper test results can only be obtained when backflow prevention assemblies are in a
static “no flow” condition during field testing. The 830-0001 and 830-0003 compensate for
leaky number 1 shut-off valves, allow for trouble shooting of shut-off valve conditions and
improve the accuracy of test results.
830-0001 Compensating Tee Assembly – A leaky #1 shut-off valve on a backflow
prevention assembly does not prevent the backflow preventer from stopping backflow but it
may prevent an accurate test. The 830-0001 is designed to compensate for a leaky #1
shut-off valve. It is plumbed in a tee configuration that allows for: connection to the test
cock of a backflow prevention assembly; connection of the high hose of the test kit to the
test cock through the assembly; and has a “bleed-off” valve which opens to atmosphere. If
the test results indicate a leaky shut-off valve the 830-0001 will help trouble shoot which
shut-off valve is leaking under what conditions. If the #1 shut-off valve is leaking this leak
can be compensated by opening the “bleed off” valve and draining the leak by the #1 shut-
off valve to atmosphere thus putting the backflow preventer in a static “no flow” condition.
When the bleed-off valve is adjusted per the test procedure the flow from the valve is the
amount of leakage by the #1 shut-off valve. The #1 shut-off valve only needs repair if the
bleed-off valve is fully open and the test still can not be passed per the procedure.
The 830-0001 has a soft seated needle valve, a quick coupler for connection to a ¼” flare
fitting at the test cock and a flare connection for connection of the test kit hose to the
assembly.
830-0003 Vertical Tube Kit – Double check valve assemblies (DCVA) do not always have
the test cocks located at the highest point of the assembly, especially when installed in a
vertical orientation. Since only a single hose is used for USC test procedures it is critical
that the test kit be held at the proper level to account for the weight of water to take an
accurate reading. If the test cock is not at the highest point on the DCVA a vertical tube
assembly must be attached to the test cock. The procedure fills the tube with water. The
test kit can then be held at the level of the water in the tube and an accurate check valve
reading can be recorded. The standard tube is 15” in height. For large assemblies or
vertical installations a 15” extension can be added for a 30” height.
Water draining from the tube or continuing for flow from the tube are indications of leaky
shut-off valves. With the use of the 830-0001 Compensating Tee Assembly and the
observations listed in the test procedures the technician can determine which shut-off valve
is leaking and under what conditions.
The 830-0003 has a quick coupler for connection to a ¼” flare fitting at the test cock. The
design is such that the tube can be rotated into a vertical orientation regardless of the
position or angle of the test cock. The 15” extension tube can be added to the assembly
without tools. The tube assemblies contain o-ring seals so a leak tight water column is
achieved.
Detailed Illustrated Test Procedures
Detailed illustrated test procedures showing the use of these type devices are only available
from the Foundation for Cross-Connection Control and Hydraulic Research – University of
Southern California.
