4.2.15 Student Book © 2004 Propane Education & Research CouncilPage 1 4.2.15 Installing & Testing Regulators Installers should know the regulator installation

4.2.15 Student Book © 2004 Propane Education & Research Council Page 1

4.2.15Installing & Testing

Regulators

Installers should know the regulator installation practices that manufacturers recommend for proper regulator operation.

In this module you will learn to identify:(1) NFPA 58 requirements for regulator installations (2) Regulator features that require protection(3) Regulator system installations(4) The use of special application regulators(5) Procedures for conducting regulator performance tests

4.2.15 Student Book © 2004 Propane Education & Research Council Pages 1 & 2

NFPA 58 Requirements for Regulator Installations

NFPA 58

2001

NFPA 58

2004

3.2.12.1 A two-stage regulator system, an integral two-stage regulator, or a two-psi regulator system shall be required on all fixed piping systems that serve ½-psig appliance systems normally operated at 11 inches water column….

Single-stage regulators shall not be installed in fixed piping systems after June 30, 1997.

3.2.12.5 The point of discharge from the required pressure relief device on regulating equipment installed outside of buildings in fixed piping systems shall be located not less than 3 feet horizontally away from any building opening below the level of such discharge… The point of discharge shall also be located not less than 5 feet in any direction away from any source of ignition, openings into direct-vent (sealed combustion system) appliances, or mechanical ventilation air intakes.

6.7.3

6.7.4.5


NFPA 58 Requirements for Regulator Installations

NFPA 58

2001

NFPA 58

2004

3.2.12.4 All regulators for outdoor installations shall be designed, installed, or protected so their operation will not be affected by the elements (freezing rain, sleet, snow, ice, mud, or debris). This protection shall be permitted to be integral with the regulator.

6.7.4.4

Regulators should be installed in new vapor distribution systems only after the successful completion of the piping pressure tests required by NFPA 58 and 54 have determined the piping system to be leak-tight. (See 3.2.22 of NFPA 58, 2001 edition.)

When regulators are replaced in existing vapor distribution systems, the system must be leak checked after the regulator is installed, and before placing appliances into gas service.


Regulator Features that Require Protection

Figure 1. Integral 2-Stage Regulator


Identifying Regulator System Installations

Figure 2. First-Stage Regulator Under Dome, Vent Sloping Down

First-Stage Regulator Installations for Aboveground ASME Tanks. Primary regulator protection of a first stage regulator consists of:

• Installation under the tank dome • Positioning the regulator with the vent

pointed or sloping downward• Verifying the vent screen is in place • Ensuring that the bonnet cap is sealed

and properly tightened

Making a loop in the pigtail connection to the tank’s service valve provides piping flexibility. The loop also serves to limit the flow of water that might be present in the propane into the regulator orifice.



Figure 3. Parallel Manifold First-Stage Regulators



First-Stage Regulator Installations for Underground ASME Tanks. Primary regulator protection of a first stage regulator consists of:

• Installation under the tank dome

• Positioning the regulator with the vent pointed or sloping downward with a U-shaped vent pipe away adapter installed to the highest point available at the top of the tank dome

• Verifying the vent screen is in place in the pipe away adapter

• Ensuring that the bonnet cap is sealed and properly tightened to prevent entry of ground water



Figure 4a. Assembly of Vent Pipe Away

Figure 4b. Forming U-Shape

Figure 4c. Installed First-Stage Regulator

Figure 4d. Pipe Away at Top of Dome



Figure 5. Manufacturer-Fabricated PVC Pipe Away Vent Assembly

The purpose of the U-shape at the top of the pipe away adapter is to create an air trap, and prevent the entry of ground water into the regulator’s upper spring case.



Figure 6. Second-Stage Regulator Installation

P r o te c t iv eC o v e r

(To p re ve n t d a m a g e fr o m fa l l in g s n o w & i c e fr o m ro o f )

S e c o n dS t a g eR e g u la t o r

Figure 7. Second-Stage Regulator with Protective Cover

Second-Stage Regulator Installations. Second-Stage regulators are typically installed outside the building in the gas service entrance piping (Figure 6). The piping layout for a particular vapor distribution system may require the installation of more than one second-stage regulator to provide service to gas appliances in locations that cannot share common piping runs.



Figure 8. Indoor (Basement) Installation

When second-stage regulators are installed inside a building, they must be vented to the outside atmosphere (Figure 8). The vent outlet must be pointed down and have a screen-protected opening.

NFPA 54

2002

5.5.1 stipulates that design operating pressure for piping systems located inside buildings shall not exceed 5 psi.

4.2.15 Student Book © 2004 Propane Education & Research Council Pages 8 & 9


2-PSI Service Regulator Installations. The installation of 2-psi service regulators is similar to the installation of second-stage regulators with two differences:

NFPA 54

2002

5.5.1 stipulates that design operating pressure for piping systems located inside buildings shall not exceed 5 psi.

1. 2-psi service regulators must be installed in combination with downstream line regulators that reduce appliance input pressure to approximately 11 inches water column.

2. 2-psi service regulators should be installed outside the building at the service entry.



Figure 9. Exchange Cylinder Regulator Installation

DOT Cylinder Regulator Installations— Knowing the operating characteristics of manual, automatic and check Tee connection fittings is important when you demonstrate the operation of the system to the customer.



Figure 10. Two-Stage Automatic Regulator

Systems (Protective Cover Removed)

Recreational Vehicle (RV) Regulators— Many campers use changeover regulators equipped with a protective cover and two portable DOT cylinders. The protective cover is used to prevent mud, water and road spray from entering regulator vents as the camper is moved around.



Recreational Vehicle (RV) Regulators— Vents of two-stage regulators installed on the ASME tank of an RV must be protected in one of two ways:

• The regulator must be installed in a ventilated compartment that provides road spray and weather protection for the regulator.

• A protective cover must be installed on the regulator to provide this protection.



Figure 11. Inspecting a Vapor Meter

Vapor Meters— Vapor meters require installation of a second-stage or 2-psi service regulator immediately before (upstream) the vapor meter.


Conducting Regulator Performance Tests

After first and second-stage regulators are installed, a system leak check should be completed as prescribed by NFPA 54, National Fuel Gas Code.

When the system has been proved to be gas tight, gas distribution lines should be purged following company procedures and the requirements of NFPA 54.

Next, appliances are placed into service according to manufacturers’ instructions to facilitate regulator performance tests.

Regulator flow pressure and lock-up tests are typically performed on

• First stage regulators (especially lock-up)

• Integral two-stage regulators

• Second-stage regulators

• Line pressure regulators



Figure 12. U-Tube Water Column Manometer

765432101234567

Figure 13. Test Tap on Integral Two-Stage Regulator

To assure that the lock-up test is valid, the regulator flow pressure test is done first, making output pressure adjustments if needed; then the lock-up test is performed with the regulator set for proper flow pressure requirements. A water column manometer, calibrated gauge or other low pressure gauging device is used to measure gas flow pressure of low-pressure regulators with output pressures of 11 to 14 inches water column.



Figure 14. Possible Manometer Test Points for Line Regulator Testing

Te st p o in t fo r2 -PSI se rvic e re g u la to r

lo c k-up te st Shuto ff va lve te st ta p :Te st p o in t # 2

To linere g ula to r

Shuto ff va lve te st ta p :Te st p o in t # 1fo r line re g ula to rflo w p re ssure a nd /o rlo c k-up te sts

Because most line regulators used in dual-pressure (2-psi) vapor distribution systems may not have outlet test taps, the manometer must be located in a piping test tap downstream of the line regulator.


Performing Flow Pressure Tests

Figure 15. Adjusting 2nd-StageRegulator Delivery Pressure

Step 1: Install a water column manometer or other suitable pressure-measuring device in the second-stage regulator outlet test tap, or in the test tap of an appliance shutoff valve at one of the appliances.

Step 2: Light all pilots and operate all appliances at full capacity.

Step 3: Check the delivered pressure shown on the manometer with the appliances operating. If necessary, adjust the delivery pressure of the 2nd-stage or line regulator to 11 inches water column with at least half of the connected appliances operating (Figure 15). Place the remaining appliances into full capacity operation.



Delivery pressure must not fall to less than the appliances’ required input pressures as given on the manufacturers’ appliance rating plates.

If adequate flow pressure is not maintained with all connected gas appliances operating, check for the following problems:

• The regulator output capacity may not be adequate to supply connected appliances

• The service regulator(s) upstream of the regulator being flow pressure tested may not be properly sized or providing sufficient output pressure for gas appliance demand.

• Piping may be too small and friction losses may be limiting the gas volume and pressure available to the appliances and/or regulator being flow tested.



Note:If any of the problems listed above are present, adjusting the output pressure of the regulator being flow pressure tested will not resolve the problem, nor provide adequate gas volume and pressure to the connected appliances. Correct the problem(s) responsible for improper gas supply. Don’t attempt to re-adjust the regulator that cannot provide required flow pressure under full demand conditions.


Performing Lock-Up Pressure Tests

Step 1: Turn all appliance controls off.

Step 2: Shut off appliance valves.

Step 3: Leave the container service valve open in order to maintain pressure on the system. With the appliance shutoffs in the “off” position, the pressure will increase slightly, then stop. This is the lock-up pressure. The lock-up pressure should not exceed the flow pressure by more than 30 percent.

Step 4: Watch the pressure for one minute. If the flow pressure was eleven inches water column, then the lock-up pressure should not exceed 14.3 inches water column.


Performing Lock-Up Pressure Tests

Figure 16a. Initial Observed Lock-Up Pressure 12.5 Inches

Figure 16b. Pressure “Creeping” Up After Initial Reading to 14.8 Inches

If pressure fails to lock-up, if manometer readings “creep” upwards over time (Figure 16), or the lock-up pressure increases beyond 30% of the flow pressure, the regulator is malfunctioning. This problem indicates the regulator must be replaced.



During the course of testing regulators, be sure to visually inspect the overall regulator installation, making sure that the regulators are properly protected as required by NFPA codes and your company’s standard operating procedures.

Regulator conditions, test pressures observed, the time (duration) of lock-up pressure tests, and regulator replacements should be documented on designated company service or inspection reports.

4.2.15 Student Book © 2004 Propane Education & Research Council Pages 16 - 21

Time to See If You Got the Key Points of This Module…

• Complete the Review on pages 16 - 18.

• See if you are ready for the Certification Exam by checking off the performance criteria on pages 19 - 21.

Documents

4.2.15 Student Book © 2004 Propane Education & Research CouncilPage 1 4.2.15 Installing & Testing Regulators Installers should know the regulator installation