TL;DR
A gas valve, in furnace and water-heater service, is the electrically operated combination control that meters fuel to the burners on command from the board or thermostat, housing redundant solenoid shutoffs, a pressure regulator, and often slow-opening or two-stage operation in one body. Manifold pressure is set at its adjustment screw — typically 3.5 inches w.c.
What it means
A gas valve, in furnace and water-heater service, is the electrically operated combination control that meters fuel to the burners on command from the board or thermostat, housing redundant solenoid shutoffs, a pressure regulator, and often slow-opening or two-stage operation in one body. Manifold pressure is set at its adjustment screw — typically 3.5 inches w.c. for natural gas, 10 to 11 for propane — and verified with a manometer, with conversion between fuels requiring a kit, not just a tweak. It is a replace-only part; opening or repairing one in the field is prohibited.
Where it sits in the glossary
Gas valve is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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