--- product_id: 34418285 title: "RELIANCE WATER HEATER CO 100112328 21\" Thermopile Assembly" brand: "reliance" price: "R1002" currency: ZAR in_stock: true reviews_count: 8 category: "Reliance" url: https://www.desertcart.co.za/products/34418285-reliance-water-heater-co-100112328-21-thermopile-assembly store_origin: ZA region: South Africa --- # 21-inch precision thermopile Lightweight 2.4 oz design Dry combustion protection tech RELIANCE WATER HEATER CO 100112328 21" Thermopile Assembly **Brand:** reliance **Price:** R1002 **Availability:** ✅ In Stock ## Summary > 🔥 Power your comfort with precision and safety! ## Quick Answers - **What is this?** RELIANCE WATER HEATER CO 100112328 21" Thermopile Assembly by reliance - **How much does it cost?** R1002 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.za](https://www.desertcart.co.za/products/34418285-reliance-water-heater-co-100112328-21-thermopile-assembly) ## Best For - reliance enthusiasts ## Why This Product - Trusted reliance brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Trusted Brand Legacy:** Manufactured by Reliance, a leader in water heater components - • **Ultra-Lightweight Build:** At just 2.4 ounces, easy to install without hassle - • **Perfect Fit for Indoor Use:** Wall mountable design tailored for indoor gas water heaters (excluding C3 FVIR models) - • **Reliable 21-inch Thermopile:** Optimized length for seamless gas water heater integration - • **Advanced Dry Combustion Protection:** Ensures safety and longevity by preventing dry firing ## Overview The Reliance Water Heater Co 100112328 21" Thermopile Assembly is a lightweight, 2.4-ounce gas-powered component designed for indoor water heaters. Featuring advanced dry combustion protection, it ensures safe and efficient operation. Manufactured by Reliance, this 21-inch thermopile is a trusted replacement part, compatible with most gas water heaters except C3 FVIR models. ## Description 25" Gas Water Heater Thermopile Assembly, Not For Use On C3 FVIR Heaters. 21", gas water heater thermopile assembly, not for use on c3 fair heaters. Review: WORKED LIKE A CHARM!! - I have a Bradford White model URG275H6N, not a Reliance brand, but it was the closest unit to my existing thermocouple that had the crimped connectors for the overtemp switch. My pilot assembly had a nut that fit around the thermocouple and screwed into a bracket. I had to cut that nut off, gently open the cut to fit the new wires into it and screwed it back it. The wire lengths were just enough and upon install, my water heater fired right up. My original problem was that the pilot light went out and wouldn't turn back on. You Tube suggested the faulty TC and was right. Saved me a minimum $300 serv call for less than $20 bucks! I'm a Happy Camper! Review: Excellent Service - The idem was exactly as described and arrived several days before it was supposed to. No issues here. ## Features - 100112328 21 inch thermopile assembly - This product adds a great value - This product is manufactured in China ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00QCCO1IW | | Best Sellers Rank | #589,768 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #1,583 in Water Heater Replacement Parts | | Brand | Reliance | | Brand Name | Reliance | | Capacity | 750 ml | | Color | Red | | Customer Reviews | 4.5 out of 5 stars 486 Reviews | | Global Trade Identification Number | 00020363175436 | | Included Components | Kitchen Faucets and Accessories, Plumbing Fixtures, faucet-cartridges | | Item Depth | 2.4 | | Item Dimensions W x H | 2"W x 2"H | | Item Highlight | Water Heater Parts, Gas Water Heater Parts, 25 in, Mexico, Carded, Natural or Propane Gas, 1 pk, Water Heaters | | Item Type Name | 21" Thermopile Assembly | | Item Weight | 2.4 ounces | | Manufacture Year | 2010 | | Manufacturer | RELIANCE WATER HEATER CO | | Manufacturer Part Number | 100112328 | | Manufacturer Warranty Description | Warranty | | Material Type | Plastic | | Model Number | 100112328 | | Mount Type | Wall | | Number of Items | 1 | | Number of Packs | 1 | | Power Source | Gas Powered | | Product Dimensions | 2"W x 2"H | | Special Feature | Dry Combustion Protection | | Special Features | Dry Combustion Protection | | Style Name | Indoor Installation | | UPC | 020363175436 | | Unit Count | 1 Count | ## Product Details - **Brand:** Reliance - **Capacity:** 750 ml - **Power Source:** Gas Powered - **Product Dimensions:** 2"W x 2"H - **Special Feature:** Dry Combustion Protection ## Images ![RELIANCE WATER HEATER CO 100112328 21" Thermopile Assembly - Image 1](https://m.media-amazon.com/images/I/71W4HUARgdL.jpg) ## Questions & Answers **Q: Does this fit rheem water heater??** A: I think that would all depend on the model number or the unit. **Q: Is this for propane or natural gas** A: Gas **Q: Hi, will this work with my sears 153.331840. Serial # 1441A01179?** A: Hi, I see that this particular heater has a newer style honeywell gas valve. The thermopile shown would probably work. If in doubt, go to the sears parts site and compare. **Q: Would it fit to a & o smith pcg 75 400 series serial no 100279911?** A: Not totally familiar with that model...best bet is to compare old with pictures of the new thermopile. Most of these thermopiles are pretty much exchangeable. Mounting maybe a bit of a problem.. But will usually fit one way or another. ## Customer Reviews ### ⭐⭐⭐⭐⭐ WORKED LIKE A CHARM!! *by J***. on July 26, 2022* I have a Bradford White model URG275H6N, not a Reliance brand, but it was the closest unit to my existing thermocouple that had the crimped connectors for the overtemp switch. My pilot assembly had a nut that fit around the thermocouple and screwed into a bracket. I had to cut that nut off, gently open the cut to fit the new wires into it and screwed it back it. The wire lengths were just enough and upon install, my water heater fired right up. My original problem was that the pilot light went out and wouldn't turn back on. You Tube suggested the faulty TC and was right. Saved me a minimum $300 serv call for less than $20 bucks! I'm a Happy Camper! ### ⭐⭐⭐⭐⭐ Excellent Service *by S***. on August 6, 2025* The idem was exactly as described and arrived several days before it was supposed to. No issues here. ### ⭐⭐⭐⭐⭐ Worked Like a Charm *by R***K on January 7, 2026* Has been working great for over 3 years now. --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.za/products/34418285-reliance-water-heater-co-100112328-21-thermopile-assembly](https://www.desertcart.co.za/products/34418285-reliance-water-heater-co-100112328-21-thermopile-assembly) --- *Product available on Desertcart South Africa* *Store origin: ZA* *Last updated: 2026-11-01*