Water Heater Gas Burner & Control Valve Parts

Gas Water Heater Control Valve and Burner Assembly Parts

When your gas water heater won't heat, won't light, or the pilot keeps going out, the problem often traces back to the gas valve assembly or burner control parts. These parts work together: the thermocouple or thermopile senses flame, the gas valve responds to that signal, and the burner assembly delivers the flame. A failed gas valve is one of the more expensive water heater repairs — but it's still cheaper than replacing the entire tank.

Control valve failures show up as no heat even when the pilot is lit, erratic temperature swings, or gas smell near the burner. OEM gas valves (, White-Rodgers, originals) maintain the exact pressure and flow your heater needs. Aftermarket valves often cause pilot issues, slow heating, or safety lockouts.

• Gas valve won't open: Thermocouple/thermopile signal weak or missing; check sensor first
• Pilot lights but heater won't heat: Gas valve solenoid failure or stuck diaphragm; requires valve replacement
• Temperature won't hold steady: Thermostatic mixing valve or control board drift; verify actual tank temp with external thermometer
• Hissing or gas smell at burner: Burner orifice clogged or valve leaking; do not ignore — potential safety hazard
• Pilot assembly won't ignite: Igniter electrode gap misaligned or igniter assembly failed; electrode must be 1/8" from burner

Gas Water Heater Control Valve & Burner Parts — Frequently Asked

What's the difference between a thermocouple and a thermopile?

A thermocouple is a simple heat sensor that generates about 25 to 30 millivolts when the pilot flame heats it. It's used on standing-pilot water heaters and furnaces — no batteries needed. A thermopile is a stack of thermocouples that generates higher voltage (500 to 750 mV) and is used on electronically controlled water heaters with ignition boards. Both fail with age; both are $10 to $20 replacements. Measure the old one or use your model number to get the right type.

How do I know if my gas valve is bad or if it's the thermocouple?

Test the thermocouple first — it's cheaper and faster. At the gas valve, disconnect the thermocouple wire and use a millivolt meter across the terminals. A healthy thermocouple reads 20 to 30 mV with the pilot lit. Below 15 mV means the thermocouple has failed. If the reading is good but the valve still won't open, the valve solenoid or diaphragm is the culprit. For electronic systems, check the igniter/control board output voltage with the model number spec sheet before condemning the valve.

Can I repair a gas valve or do I have to replace it?

Most OEM gas valve assemblies are sealed units designed for replacement, not repair. You can clean the burner orifice (tiny hole that meters gas) with a fine wire, but internal valve parts like the solenoid coil and diaphragm aren't user-serviceable. Always use the OEM replacement for your brand and model and other major brands White-Rodgers, and brand-specific valves have different inlet/outlet pressures and thread sizes.

Why does my pilot light go out after I release the knob?

The thermocouple isn't generating enough signal to hold the solenoid open. Hold the knob in for 30 to 60 seconds to fully heat the thermocouple, then release slowly. If it still goes out, the thermocouple is weak or the solenoid is failing. A new thermocouple fixes 80% of these cases. If a new thermocouple doesn't solve it, the gas valve solenoid itself has failed and requires valve replacement."

Easy Online Ordering for Water Heater Gas Burner & Control Valve Parts

Efficient hot water heater repair starts with the right parts. Find genuine Water Heater Gas Burner & Control Valve parts online. Our parts are designed for easy replacement and repair, perfect for both homeowners and professional technicians. Take advantage of same-day shipping to ensure your hot water is back in no time. Use our convenient model number or part number lookup to find the exact replacement part you need. Whether you need a gas control valve or a burner replacement, order online today and address your water heater repair needs quickly. For additional repair guidance, browse our Water Heater Repair Help section. For related parts, visit our page on Water Heater Gas Burner Control Valve Parts.

Model Number Basics for Water Heaters

Check the label on your water heater for its model number, usually near the gas valve or thermostat, on the side of the tank, or on the outer jacket. Turn off the burner and let nearby surfaces cool before inspecting the label. The model number identifies the complete water heater, not just its gas burner or control valve, so it is the key to matching parts across the entire unit. Enter it in the model number search, and the catalog will pull up parts matched to your water heater. This narrows the selection quickly, helps you avoid mixing up gas and LP parts, and makes it easier to order with confidence.