Standard
Operating Procedure Effective Date: REVISES
5/23/91 AUTHORITY: SOMERSET GAS SERVICE SUBJECT:
TESTING PROCEDURES
Testing Procedure for low pressure
house piping
POLICY: Although gas service
technicians may not do the actual testing, they are
responsible for supervising and setting the limits for this
testing by plumbers and other installers.
Among the
kinds of tests which are performed on house piping, that is,
piping from the meter to the appliance, are:
- testing new or partially replaced low pressure house
piping
- testing existing low pressure house piping
PROCEDURE I:
Testing Procedures For
New or Partially Replace Low Pressure Piping According to
the National Fuel Gas Code Z 223.1 the following procedures
should be observed when testing new or partially replace house
piping with an operating pressure below 1 pound. (Base
pressure measured to a customer is usually below ½ pound.)
- Close all manual shutoff valves ahead of appliances, or
disconnect and cap outlet.
- Connect the testing instrument to the inlet of the
piping (see Fig. 1) to be tested. Acceptable testing
instruments include a properly calibrated gauge, a mercury
manometer, or a slope gauge which will read in increments of
not greater than one-tenth pound.
- Using air, pressurize the house line to at least 6.0
inches mercury or 3.0 pounds gauge pressure. The piping may
also be filled with fuel gas or inert gas but with NO
OTHER gas or liquid. OXYGEN SHALL NEVER BE USED!
- The source of pressure shall be isolated before pressure
observations are made.
- This test shall be maintained for a minimum of 10
minutes with no drop in pressure.
- Loosen gauge and reduce pressure to "zero" on the
piping.
- Open shutoff values to all connected appliance.
- Turn off all pilot and main burner values (see note) on
appliances.
NOTE: If pilot or main burner valves are
not part of the appliance, then proceed with soap testing of
the section of the house piping from the shut off valve to
the appliance under system operating pressure.
- Close gauge opening and pressurize the house piping to
not less than 10.0 inches nor more than 14.0 inches water
column.
- The source of pressure shall be isolated before pressure
observations are made.
- Maintain this pressure for a minimum of 10 minutes
without showing any drop I pressure. This pressure shall be
measured by an acceptable test instrument described in Step
2.
- Remove pressure and test instrument from piping.
- Reconnect all piping and the meter.
- When meter is installed and gas pressure applied, test
all exposed joints on meter setting with a soap-and -water
or leak-detecting solution. NEVER USE AN OPEN FLAME.
- Purge piping of any possible air. Note: DO NOT PURGE
INTO ANY CLOSED AREA OR COMBUSTION CHAMBER.
- Record test results for verification on company ticket
or work order.
- Handle any leak in accordance with company policy and
procedures.
- Repeat tests when leaks have been repaired.
PROCEDURE II
Testing Procedures For
Existing Low Pressure House Piping
The following
procedures should be observed when testing existing low
pressure house piping with an operating pressure below 1
pound.
- Remove meter from the meter loop.
- Connect the test instrument to the inlet of the piping
to be tested.
- Turn off all pilot and main burner valves on appliances.
Cap all outlets.
- Close gauge opening and pressurize the house piping to
not less than 10.0 inches water column nor more than 14.0
inches water column.
- The source of pressure shall be isolated before pressure
observations are made.
- Maintain this pressure for a minimum of ten minutes
without showing any drop in pressure. This pressure shall be
measured by the proper test instrument.
- Remove pressure from piping and remove test instrument.
- When meter is installed and gas pressure applied, soap
all exposed joints with a soap and water solution. (NEVER
USE AN OPEN FLAME.)
- Test results must be recorded for verification.
- Any leak shall be handled in accordance with your
companies policy and procedure and test repeated.
REVISED 5-23-91
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