How does air get in lines

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grider

New Member
Mar 26, 2023
3
Florida
How does air get into natural gas lines while away on vacation for extended periods? My stove is fed from a utility company that provides natural gas to the neighborhood. If my stove remains unused for months, it becomes necessary to purge the air from the system. Are there tiny air bubbles that propagate through the lines and collect at the highest point over time? That doesn't seem to make sense because natural gas is lighter than air. So what causes this?
 
I think I found the answer. Compressed Natural Gas is heavier than Compressed Air. So I guess it is indeed tiny air bubble collecting at the highest point over time. At least I cant think of another explanation . . .
 
I've never heard of this problem. It certainly is not normal. Who is your gas supplier? Do you routinely shut off any parts of the gas piping?