Lennox 13H33

GAS VALVE 24 VAC 1/2IN NPT FOR ELECTRO

American National Standard Pipe Thread standards, often called National Pipe Thread ("NPT") standards for short, are U.S. national technical standards for screw threads used on threaded pipes and pipe fittings. They include both tapered and straight thread series for various purposes including rigidity, pressure-tight sealing, or both. The various types are each named with a symbol and a full name; examples of the symbols include NPT, NPS, NPTF, NPSC, and others.

Valves are widely used in different restaurant equipment designs. A valve is a device that regulates, directs or controls the flow of a fluid (gases, steam, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. In an open valve, fluid flows in a direction from higher pressure to lower pressure. 

Valves may be operated manually, either by a handle, lever, pedal or wheel. Valves may also be automatic, driven by changes in pressure, temperature, or flow, allowing control over a variety of operational requirements.