Which component is used to regulate gas pressure in a gas piping system?

• A. Thermocouple
• B. Valve
• C. Regulator
• D. Damper

Answer: (C)

Regulation of gas pressure in a piping system is accomplished by a regulator. The regulator automatically reduces the high supply pressure to the much lower pressure required by appliances and maintains that pressure as demands change. It does this with a sensing element (like a diaphragm) and a spring that set a target downstream pressure; when downstream pressure tends to rise, the regulator closes slightly to throttle gas, and when it drops, it opens to allow more gas, keeping the pressure steady.

A thermocouple is a flame-safety sensor and does not control pressure. A valve can control flow or shut off gas but without the automatic feedback to hold a set pressure, so it doesn’t reliably regulate pressure on its own. A damper controls air flow for combustion or venting, not the gas pressure itself.