The best hot water tank gas valve is the one that matches the water heater’s exact model and the valve’s part number, gas type, and physical dimensions. The Reliance 100112336 options suit buyers checking that part number; the ClimaTek WT8840B1000 is a direct replacement for that model number, while its WV8840B1158 valve is for a different specified part. The 110-326 kit is a natural-gas option with a thermocouple. Have a qualified professional verify the match and install a gas control valve.
| Product | Best suited for | Key detail |
|---|---|---|
| Reliance 100112336, Resideo-made | Buyers matching 100112336 | WT8840B, 1-inch cavity |
| Reliance 100112336 thermostat | Listed A.O. Smith, Reliance, State, and American heaters | Natural-gas control valve |
| ClimaTek WT8840B1000 | Replacing WT8840B1000 | Listed as a direct replacement |
| ClimaTek WV8840B1158 | Replacing WV8840B1158 | Natural gas, 2-inch cavity |
| 110-326 valve kit | Buyers needing a natural-gas valve and thermocouple | 1-3/8-inch shank |
Reliance 100112336 Resideo Gas Control Valve
This valve is best for buyers whose existing water heater calls for Reliance part 100112336 or the corresponding WT8840B configuration. The listing identifies it as a 160-degree-F valve with a 1-inch cavity, made by Resideo. Those identifiers make it easier to compare against an existing valve or the heater’s parts documentation.
The listed ambient temperature range is 0°C to 60°C. Verify the full model and connection details before ordering; a shared brand or similar appearance does not establish compatibility. This product is a gas control component, so professional installation is the safer choice. Avoid this option if your heater requires a different part number, cavity size, or gas type.
Reliance Natural Gas Valve And Thermostat
This Reliance 100112336 thermostat and natural-gas control valve is best for buyers with an A.O. Smith, Reliance, State, or American-branded water heater that specifies this replacement part. The listed brand compatibility is useful as a starting point, but the heater’s exact model and existing valve number should still be checked.
The product information advises professional installation and warns that homeowner installation may potentially affect warranty coverage. It also states that the product is manufactured in China. Choose it if the natural-gas specification and replacement number match your unit; do not assume it fits every heater from the named brands.
ClimaTek WT8840B1000 Replacement Valve
This ClimaTek valve is best for a buyer replacing the specific WT8840B1000 part. The listing describes it as a new, upgraded water heater gas valve and says it directly replaces WT8840B1000. It also identifies the intended setup as a tank with 1-inch insulation.
Part-number matching is the main reason to consider this option. Confirm the complete number on the old valve and check the water heater documentation before purchasing. The listing’s replacement claim does not establish that it fits other WT8840B versions or different cavity sizes. Avoid it if your unit calls for another valve number.
ClimaTek WV8840B1158 OEM Upgraded Valve
This option is best for buyers whose equipment specifies WV8840B1158. The listing describes it as an OEM upgraded natural-gas valve and says it directly replaces that part number. It also identifies a 2-inch cavity, making cavity size an important comparison point alongside the part number.
Choose this valve only after verifying the model marking and required cavity against the existing part or heater documentation. Its 2-inch cavity specification differs from the 1-inch options in this guide. A similar appearance or the same general purpose is not enough to confirm fit.
110-326 Natural Gas Valve Kit With Thermocouple
This 110-326 kit is best for buyers whose heater calls for a natural-gas valve with a 1-3/8-inch shank and who also need a replacement thermocouple. The listing specifies a 3-1/2-inch water column, 1/2-inch inlet, and 1/2-inch inverted-flare outlet with a right-hand thread.
Check every connection and dimension against the original equipment before selecting it. The listing cautions that the included thermocouple may not fit all equipment, even though it does not affect use of the valve body. Avoid this kit if your heater requires a different gas type, shank length, or connection arrangement.
Buying Guide: How To Choose A Water Heater Gas Valve
How do I confirm the correct replacement?
Start with the water heater’s model and serial label, then look up its parts documentation or consult a qualified technician. Compare the complete part number printed on the existing valve with the replacement listing. Check the gas type, cavity size, shank length, inlet and outlet connections, and other listed specifications. Do not choose a valve based only on appearance or manufacturer name.
Why do cavity size and connections matter?
The products here include 1-inch and 2-inch cavity descriptions, plus a kit with specified shank and port dimensions. These details can distinguish parts that otherwise seem similar. A mismatch can prevent proper installation. Confirm the measurements required for your particular heater rather than treating a product’s dimensions as universal.
Should I install a gas control valve myself?
Use a qualified professional for gas valve replacement. The Reliance listing specifically advises professional installation, and incorrect work on gas equipment can create safety risks. Follow the water heater manufacturer’s instructions and applicable local requirements. If you smell gas, leave the area and contact your gas utility or emergency services from a safe location.
Frequently Asked Questions
Are all hot water tank gas valves interchangeable?
No. A valve must match the heater’s specified part number, gas type, dimensions, and connection requirements.
Can I use a natural-gas valve on a different gas type?
Do not assume so. These listings identify natural-gas products where stated. Confirm the required gas type in the heater documentation before buying.
Does the thermocouple come with every valve?
No. The 110-326 listing includes a replacement thermocouple. The other product details here do not state that one is included.
What should I do if I cannot find my valve number?
Use the water heater model information to consult its parts documentation or ask a qualified technician to identify the correct replacement.