One of the most misunderstood portions of the commercial heating system is the gas train. The gas train is a series of components that safely feed natural or propane gas into the burner.
The first component of the gas train is the sediment trap, more commonly referred to as the “dirt leg.” This is used to catch any dirt or moisture that may be entrained in the natural gas feed to the building. It is typically a nipple and cap located on the run of the tee. The gas feed is on a right angle coming from the bull of the tee.