Here at Able Skills we are also trying to give our students as many recourses as possible. This tutorials page can be used as an extra reference for our engineers in training and as an insight for those interested in the trade. In this tutorial we will look at 'How to carry out a Low pressure tightness test'.


Step One:


The initial step in this process will be making sure all of the appliances in the whole installation are switched on. Otherwise you will not get a fair reading. As Sam mentions in the video if the cooker in the installation has a drop-down lid, make sure it is up. Check there are no open ends on any pipework.


Step Two:


Next, grab your text gauge and make sure that it is in good nick. Make sure there is no damage to the hose and ensure there is water within the gauge and that it's level on zero. Remember whenever we are putting equipment on to a gas system make sure the supply is switched off.


Step Three:


Now it's time to remove the test nipple and attach the test gauge through the hose. The first part of the test is checking whether or not the emergency control valve is working correctly. To do this, slowly open the valve and keep your eyes on the test gauge you are looking for a reading between 7 - 10 Millibar. Let this sit for 1-minute to ensure you gain a correct reading. 


Step Four:


Now it is time for the Tightness Test itself. Again, slowly release the emergency control valve and allow for the pressure in the gauge to reach between 20 - 21 Millibar. Then let that run for another 1-minute temperature stabilisation period.


Step Five:


Return to the gauge, if there is no movement outside of the 20 - 21 Millibar range then it is gas tight. This is great and means there seems to be no leaks or issues.

Step Six:


The final step before removing your test gauge will be opening the emergency control valve fully. This is to identify the standing pressure. Do this slowly but open the valve all the way. Sam identifies a standing pressure of 24.5 Millibar.


If you have not locked out the Gas meter regulator that means you have properly been testing the entire installation. Now, turn the Gas supply back off and remove the test equipment. Finally re-attach the test nipple.


Step Seven:


The test is now complete! The only part of the installation not tested for Gas tightness is the test nipple itself. To do this have some leak detection fluid/spray handy and apply it to the nipple and open the gas supply once more. If there are any leaks the spray would bubble up. Turn the gas supply off for a final time and wipe of any excess leak detection fluid.



Additional Information:


Remember that conducting gas work without being registered with the Gas Safe Register is illegal. These tutorial videos are mainly for our training students as an extra resource to refer to whilst they continue on their training journey with us. If you would like some more information about the varies Gas training courses that we offer call us on 01322 280 202! 


We offer a whole range of Gas training courses. We have options available for both new entrants looking to start a career in the trade and options for working engineers such as ACS exams. We offer only the best training options and qualifications through BPEC