(Low Pressure Testing Procedure)
In this method a low pressure test gauge (ECII 2434A) or a Water manometer ( 1212Kit ) is used to detect pressure loss due to leaks.
Step 1. Inspect all connections and appliance valves to be sure such connections are wrench tight and that all appliance connections are closed including pilot valves and all line shutoff valves.
Step 2. Connect low pressure test gauge or manometer to a range top burner orifice. If a range is not available a special tee may be installed between the appliance shut-off and inlet to the appliance. Several shut off valves have a pressure tap port that may be used.
Step 3. Open container valve to pressure piping system. Leave it open for two or three seconds then close tightly. Return to appliances and open each appliance piping shut-off valve slowly. If the pressure drops below 10 inches water column repeat step 3.
Step 4. Observe indicated pressure on low pressure test set or manometer. This reading should be at least 11 inches water column. Now slowly open one burner valve on an appliance or bleed through a pilot valve enough gas to reduce pressure reading on the test set or water manometer to exactly 9 inches water column.
A 10 minute constant pressure indicates a leak tight system. A drop in pressure indicates a leak in the system. If a drop occurs, check joints and other possible points of leakage with an approved combustible gas detector, Liquid Leak Detector, soap and water, or an equivalent non-flammable solution. CAUTION: Since some leak test solutions, including soap and water, may cause corrosion or stress cracking, the piping should be rinsed with water after testing, unless its determined the leak test solution is non-corrosive. Never test with an open flame. If there is an increase in pressure it indicates the container valve is not shut off completely. Shut off container valve tightly and repeat step 4. It is wise to install a redundant shut-off valve at the tank valve outlet to ensure that there is no seepage through the container valve's stem seat and valve body.
B. Gauge Adapter Method (High Pressure Testing Procedure)
Step I . Inspect all connections and appliance valves to be sure such connections are wrench tight and that all appliance valves are closed including the pilot valves.
Step 2. Install a ECII (Rego) 2962 high pressure test gauge adapter on the tank service valve and connect the other end of the gauge adapter to the pigtail and regulator inlet.
Step 3. Open container valve to allow the system to pressurize while observing indicated pressure on 300 pound testing gauge.
Step 4. Close service valve tightly. Note pressure reading on the pressure gauge, then slowly bleed gas between service valve and gauge adapter, reduce pressure by 10 pounds per square inch and retighten gauge adapter into service valve, note reading on gauge.
If gauge reading remains constant for 10 minutes it can be assumed the system is leak tight. If the pressure reading drops, It indicates a leak somewhere in the high or low pressure piping system. NOTE: A pressure drop of 15 psig in 10 minutes time, indicates a leak as little as 10 BTU of gas per hour. Check joints and other possible points of leakage with an approved combustible gas detector, liquid leak detector, soap and water, or an equivalent non-flammable solution.
CAUTION: Since some leak test solutions, including soap and water, may cause corrosion or stress cracking, the piping should be rinsed with water after testing, unless its determined the leak test solution is non-corrosive. Never test with an open flame. If there is an increase in pressure it indicates the container valve is not shut off completely. Shut off container valve tightly and repeat step 4.
Step 5. Disconnect the 2962 test gauge adapter from the service shut off valve. Reconnect pigtail, tighten and test with soap and water or an appropriate leak detector solution, (refer to caution in 4. above). Step 6. Proceed with manometer method, steps 2 through 4. Never check for leaks with an open flame.
NOTE: After the piping system and appliance connections have been proven to be leak tight, the air may be purged from lines . Refer to NPGA safety handbook section 403 and NFPA 54 for more information, or the B149 Installation Code.
Regulator Delivery Pressure
Check the regulator delivery pressure with approximately half the total appliance load in use. Your gauge should read 11 inches water column (or 6 1/3 ounces per square inch) at the appliance. Adjust regulator if necessary, following this, turn on all appliances to make sure that pressure is maintained at full load. If an excessive pressure drop occurs, inspect line for "kinks", "flats" or other restrictions.
CAUTION: Appliance regulators are installed on most appliances and may be preset by the manufacturer for flow pressure lower than 11 inches water column, it is recommended the manometer or test gauge be installed at a location other than the range orifice or appliance pressure tap when performing lock-up and delivery pressure checks.
Regulator Lock-up and Leakage
After this, shut off all appliance valves to determine if the regulator has a worn seat or if it has been set too high to compensate for line losses due to undersized piping. A slight rise in pressure will occur under these conditions. This is called the "lock-up" pressure. The lock-up pressure should not exceed 120% of the set delivery pressure for the given tank pressure. A quick rise in pressure above this point will indicate undersized piping.
Continue this same test for 5 minutes or more. If a creeping rise is noticed in the pressure, the regulator seat is not closing off properly. Inspect regulator inlet nozzle for dirt, scratches or dents and seat disc for signs of wear. Replace where necessary.
For more information, refer to NFPA 54, Section on Inspection, Testing and Purging, NPGA Safety Bulletin 403 pressure testing and leak checking LP Gas piping system. For more information on setting single stage regulators, request Rego Products Technical Guide 107.
Leak Testing an Existing System Being Placed Back in Service
According to NFPA 54, Appendix D (1992 Edition), leak checks on systems being placed back in service should include all regulators, including appliance regulators and control valves in the system. All shut-off valves found before the appliances should be turned on for the leak check as well as the appliance control valve that utilizes 100 % pilot shut-off valves. This test will help prove the integrity of the 100 % pilot shut-off valve for each appliance.
If there are appliances that are not equipped with a 100% pilot shut-off system, the manual gas valve should be placed in the off position prior to leak testing.
A. Manometer Method
Step I . Insert a water manometer or equivalent device (ECII -Rego 1212Kit or 2434A) into the system downstream of the final stage regulator.
Step 2. Pressurize the system with LP-Gas or Air to a test pressure of 11 " water column. This can be accomplished by opening the container valve for two or three seconds then closing tightly. If the pressure reading on the test device is below 10" w.c., repeat this step.
Step 3. Observe the pressure indicated on low pressure test device, it should read at least 11" w.c.. Release enough pressure through an appliance burner valve or other suitable means to drop the system pressure to 9" w.c.. There should be no loss or gain in pressure for a period of 3 minutes.
If leakage is indicated by a drop in pressure, check all equipment or outlets for leaks. If they are leak-free, check all joints and other possible points for leakage with an approved combustible gas detector, soap and water, liquid leak detector or an equivalent non-flammable solution. If there is an increase in pressure, it indicates the container valve is not shut off completely. Shut off container valve tightly and repeat Step 3.
CAUTION: Since some leak test solutions, including soap and water may cause corrosion or stress cracking, the piping should be rinsed with water after testing, unless its determined the leak test solution is non-corrosive. Never test with an open flame.
B. Gauge Adapter Method
Step 1. Insert an ECII Rego 2962 high pressure test gauge adapter between the container gas shut-off valve and the inlet of the first stage regulator in the system.
Step 2. Open container valve while observing indicated pressure on the 300 pound testing gauge. Allow the system to pressurize and close the container shut-off valve.
Step 3. Slowly bleed enough gas from the system to lower Pressure reading by 10 psig. Note reading on gauge. Allow this test to stand for 3 minutes without showing an increase or decrease in pressure.
If leakage is indicated by a drop in pressure, check all equipment or outlets for leaks. If they are leak-free, check all joints and other possible points for leakage with an approved combustible gas detector, soap and water, or an equivalent non-flammable solution. If there is an increase in pressure, it indicates the container valve is not shut off completely. Shut off container valve tightly and repeat Step 3.
CAUTION: Since some leak test solutions, including soap and water, may cause corrosion or stress cracking, the piping should be rinsed with water after testing, unless its determined the leak test solution is non-corrosive. Never test with an open flame.
