For a propane water heater, choose a burner assembly labeled LP or propane and match its part number, burner length, and orifice to your heater. The A.O. Smith 100112352 is an 18-inch LP burner assembly, while the A.O. Smith 100112347 is a 16-inch LP assembly. The SURIEEN product is an LP pilot assembly, not a main burner. The natural-gas burner assemblies below are included for comparison only and are not suitable propane replacements.
| Product | Fuel and part type | Best suited for |
|---|---|---|
| A.O. Smith 100112352 | LP burner, 18-inch, #51 orifice | Compatible heaters requiring this exact assembly |
| A.O. Smith 100112347 | LP burner, 16-inch, #51 orifice | Compatible heaters requiring a 16-inch LP assembly |
| SURIEEN LP Pilot Assembly | LP pilot assembly | Matching forced-air heater pilot replacement |
| A.O. Smith 100112342 | Natural-gas burner, 16-inch, #37 orifice | Natural-gas heaters only |
| ZAWANEX 100112342 replacement | Natural-gas burner, 16-inch, #37 orifice | Natural-gas heaters only |
A.O. Smith 100112352 18-Inch LP Burner Assembly
This A.O. Smith assembly is specified as an LP burner with an 18-inch configuration and a #51 orifice. It is the most directly relevant option in this list for a propane water heater that calls for part 100112352 and those specifications.
Best for: Owners or repair professionals replacing an existing 100112352 assembly in a heater whose parts information confirms an 18-inch LP burner with a #51 orifice. It was selected because the listed features explicitly identify LP fuel and a main burner assembly.
Check before ordering: Confirm the heater model and original part number, along with burner length and orifice designation. Do not assume that an 18-inch assembly will fit a heater that uses a 16-inch burner.
Limitation: The supplied listing information gives only the part description and does not provide a model-by-model compatibility list. Match the heater documentation or existing part rather than relying on appearance alone.
A.O. Smith 100112347 16-Inch LP Burner Assembly
The A.O. Smith 100112347 is listed as a final burner assembly for LP, with a 16-inch configuration and a #51 orifice. Compared with the 18-inch 100112352, this is the better choice only when the heater calls for the shorter 16-inch assembly.
Best for: A compatible propane water heater whose original burner or parts documentation specifies A.O. Smith part 100112347, a 16-inch burner, and a #51 orifice. It was selected because it is explicitly an LP main burner assembly rather than a natural-gas part or pilot component.
Choose this if: Your old assembly’s part number and dimensions match the listing. Compare the exact part number and fuel type before purchase; similar-looking burner assemblies can have different fuel-specific orifices.
Limitation: The provided features do not state which heater models use this part. The 16-inch length alone is not enough to establish compatibility.
SURIEEN LP Propane Pilot Assembly
This SURIEEN product is a propane pilot assembly, not a main burner assembly. Its listing names several forced-air heater models and brands, including Desa, Reddy, All-Pro, Universal, NR, Sears, and Remington. It also advises buyers to compare the original part’s size before replacement.
Best for: Someone replacing a pilot assembly on a listed or otherwise confirmed compatible LP forced-air heater. It is included because pilot components are sometimes confused with main burner assemblies during repair searches, but it does not replace the main burner.
The listed construction includes brass and zinc alloy. The product information also warns against sharply bending the thermocouple line near the crimped section, since damage there may cause an electrical problem. Installation may require adjustment to the mounting bracket.
Limitation: The listed compatibility is for specified forced-air heaters and does not establish suitability for every propane water heater. Verify the appliance type, original component size, and part requirements before ordering.
A.O. Smith 100112342 Natural-Gas Burner
This A.O. Smith assembly is a 16-inch natural-gas burner with a #37 orifice. It is not a propane burner and should not be selected for an LP water heater. The listing is useful as a fuel-type comparison: a similar-looking assembly can have a different orifice and be designed for a different gas.
Best for: A compatible natural-gas water heater whose parts documentation specifies 100112342, a 16-inch burner, and a #37 orifice. It was selected to help prevent a common ordering mistake when buyers search broadly for a water heater burner assembly.
Avoid this if: Your heater uses propane or its original part specifies LP. The listing identifies this assembly as natural gas; it is not a substitute for an LP burner.
Limitation: Its listed fuel designation makes it unsuitable for the propane-focused need addressed by this article. Do not modify orifice components to try to convert the assembly.
ZAWANEX 100112342 Natural-Gas Replacement
ZAWANEX describes this product as an aftermarket replacement for 100112342 and the earlier part number 9007899005. The listed configuration is natural gas, a 16-inch burner, and a #37 orifice. The manufacturer advises comparing the original part number, water heater model, and serial number before ordering.
Best for: A natural-gas heater confirmed to use 100112342 or 9007899005 and the specified 16-inch, #37 configuration. It was selected as a clear example of a replacement that shares some burner dimensions with LP products but is explicitly not designed for propane.
Avoid this if: You need an LP or propane burner. The product features state that it is for natural gas only and warn against changing the supplied orifice to convert fuel types.
Limitation: This is not a propane-compatible option. Its fit depends on confirming the exact part and heater details, not merely matching burner length.
Buying Guide: How to Choose a Propane Burner Assembly
How can you tell whether a burner is for propane?
Look for an explicit LP or propane designation in the part description and on the heater’s documentation. Do not infer fuel compatibility from a product image, brand name, or burner length. In this product list, the 100112347 and 100112352 assemblies are identified as LP; the 100112342 assemblies are identified as natural gas.
Fuel type matters because burner assemblies can use different orifices and configurations. A natural-gas assembly is not a safe substitute for an LP assembly just because the parts look alike. Never attempt to convert a burner by drilling, replacing, or modifying an orifice unless the appliance manufacturer’s instructions specifically call for an approved conversion procedure.
Should you choose a 16-inch or 18-inch burner?
Use the burner length specified for your heater and replacement part number. The A.O. Smith 100112347 is listed as a 16-inch LP burner, while the 100112352 is listed as an 18-inch LP burner. Length is an important comparison point, but it does not prove that a part fits a particular heater.
Check the old assembly, appliance label, and manufacturer parts documentation. If a burner is damaged or its label is unreadable, have a qualified service professional identify the correct replacement rather than choosing based on approximate measurements.
Why does the orifice number matter?
The listed LP burner assemblies use a #51 orifice, while the natural-gas 100112342 assemblies use a #37 orifice. The different specifications are a reminder that an orifice is tied to the intended fuel and burner design. Match the complete part specification, not only the fuel label or dimensions.
Do not replace or alter an orifice to make an incompatible burner work. If the heater’s documented specification conflicts with a product listing, pause and verify the correct part with the appliance manufacturer or a qualified technician.
What information should you verify before ordering?
- Fuel: Confirm that the appliance uses LP/propane, not natural gas.
- Part number: Compare the number on the old assembly with the heater’s parts documentation.
- Model and serial number: Use these details to check the correct replacement for the specific heater.
- Burner size and orifice: Match the documented length and orifice specification.
- Part type: Distinguish a main burner assembly from a pilot assembly or thermocouple component.
When is a pilot assembly the right part?
A pilot assembly serves a different function from the main burner assembly. The SURIEEN listing is an LP pilot replacement for specified forced-air heaters; it is not a substitute for a water heater’s main burner. The Fixitshop product in the supplied listings is a natural-gas pilot assembly with 24-inch tubing, so it is not an LP burner option and is not included among the selected propane products.
Before buying a pilot component, identify the appliance type and compare the existing part’s connections, dimensions, and model compatibility. Do not assume that a pilot assembly described as universal will fit every heater.
When should installation be handled by a professional?
Gas appliance repairs involve fuel connections and combustion components. If the replacement instructions are unclear, the gas type is uncertain, or a correct part cannot be verified, use a qualified service professional. Follow the appliance manufacturer’s installation and safety directions, and do not operate a heater with a suspected gas leak, damaged burner, or unverified fuel conversion.
Frequently Asked Questions
Can I use a natural-gas burner assembly in a propane water heater?
No. The natural-gas 100112342 assemblies are identified as natural-gas parts, not LP parts. Select a burner specifically designated for propane and matched to the heater’s required part number and specifications.
Which listed products are main propane burner assemblies?
The A.O. Smith 100112352 is an 18-inch LP burner assembly with a #51 orifice. The A.O. Smith 100112347 is a 16-inch LP burner assembly with a #51 orifice. Confirm the appliance’s documented part requirements before choosing between them.
Is the SURIEEN product a water heater burner?
No. It is described as an LP pilot assembly for specified forced-air heaters. A pilot assembly and a main burner assembly are different parts and are not interchangeable.
Does a matching burner length guarantee compatibility?
No. Burner length is only one specification. Fuel type, part number, orifice, heater model, and serial number should also match the appliance requirements.
Can I change a natural-gas burner into a propane burner by changing the orifice?
Do not modify the listed assembly for that purpose. The ZAWANEX product information specifically identifies its assembly as natural-gas-only and warns against changing its supplied orifice to change fuel type. Use the correct manufacturer-approved LP part.