Pressure build up inside a gauge can happen and is very natural for a liquid filled gauge. The pressure build up (usually very minimal) can sometimes cause the needle to move off of zero and/or cause the gauge to read inaccurately. This video will quickly show you how to "burp" the pressure gauge to get your needle back to zero. If you have further questions or would like to learn more about Kodiak Controls, visit our website at https://kodiakcontrols.com.