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Step 1. Turn inlet valve 90º clockwise to Step 2. Turn outlet valve 180º counter clockwise to
Step 3. Turn inlet valve clockwise 90º to
Position 1.
Position 2.
Position 3.
Step 5. Turn outlet valve 180º clockwise to
Step 6. Turn inlet valve 90º counterclockwise to
Position 4.
Position 5.
Inlet valve at position 5, outlet valve at
position 4 (both arrows toward meters).
Normal Operating Flow Mode
Bypass Flow Mode
Meter Maintenance
PROCESS 1
PROCESS 4
PROCESS 3
PROCESS 2
Purge Mode
Back To Normal Operation Flow Mode
SHUT OFF POSITION
WARNING:
This position will shut-off the flow of gas and require shut-off
procedure and pilots re-lit.
Step 4. 1. Fully assemble meter to the bar. 2. Remove purge port plug to allow gas to flow to atmosphere (reference figure above for purge port location).
3. Slowly turn inlet valve to Position 1. 4. Purge meter until the smallest increment dial makes two full revolutions. 5. Replace purge port plug once meter
is purged.
DO NOT PURGE IN CONFINED SPACE.
Perform required maintenance to the meter, when the meter change out or meter maintenance has been completed, purge the air out of the new meter
before taking the meter bar out of bypass mode.
To stop the flow of Gas to meter and structure, turn valves to Position 3 & 4.
Natural Gas
6480 By-Pass Procedure
NOTE:
Failure to follow this procedure may result in interrupted gas service and loss of pilot lights.
NOTE:
It is recommended that a manometer be installed at the downstream pressure tap prior to operating the bypass. The manometer will monitor the downstream pressure. In
the event the pressure drops below your stated system requirements, an improper sequence may have occurred. The valves should be returned to normal operation immediately
to restore flow of gas. Once pressure is restored, the bypass procedure can then be started again. If the pressure drops below your stated system requirements at any time,
pilots need to be checked and possibly relit.
- Bypass application only at regulated pressure.
- Follow all applicable codes and procedures.
5/21
3210-538
By-Pass Mode
PATENT 7,347,219
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5
Downstream
Pressure Tap
Purge Port
