Finding the right replacement or upgrade for an old gas water heater? This guide highlights five practical options, focusing on gas-fired and propane tankless models and valve components that fit many systems. These picks are suitable for homeowners, RV travelers, and those seeking efficient hot water on demand. Each product is explained with who it’s best for, why it was selected, and a clear limitation to consider.
Summary table of chosen products
| Product | Brand | Best For | Why It Stands Out | Limitations |
|---|---|---|---|---|
| Gas Control Valve 100112336 | Reliance | Homeowners needing replacement valves | Compatibility with major brands; professional installation recommended | Warranty may require professional install |
| Liquid Propane Valve 100112338 | Reliance | Propane-based systems | Value-focused valve for old systems | China-made |
| Rinnai RX199iN Condensing Tankless | Rinnai | Homes needing high flow and space efficiency | Condensing design, up to 11.1 GPM, indoor/outdoor flexibility | More complex installation |
| FOGATTI Natural Gas Tankless 7.5 GPM | FOGATTI | Compact homes needing on-demand hot water | High BTU, compact footprint, instant heating | May require proper venting |
| Orbek RV Tankless Water Heater | Orbek | RV users needing portable on-demand hot water | 12V DC, remote control, high efficiency | RV-specific installation dimensions |
Reliance Gas Control Valve 100112336
The Reliance Gas Control Valve 100112336 is a gas valve replacement option for systems from A.O. Smith, Reliance, State, and American brands. It is intended for professional installation, a factor often important for maintaining warranties on older gas water heating systems. It represents a straightforward path to restoring safe gas control in aging units. Best for homeowners who have access to a licensed installer and want to keep existing gas-fired equipment running. A limitation is that homeowner installation can void warranties, depending on the model and local codes.
Reliance Liquid Propane Valve 100112338
The Reliance Liquid Propane Valve 100112338 is a liquid propane gas valve designed to fit relevant Reliance and AO Smith configurations. It adds value by enabling continued operation of propane-based gas water heaters in older homes. Best for households using LP gas with a need to replace a faulty valve. Note that compatibility with specific models is essential; verify your unit’s valve type before purchase.
Rinnai RX199iN Condensing Tankless
The Rinnai RX199iN is a condensing tankless water heater suitable for indoor or outdoor installation. It offers up to 11.1 GPM and supports propane or natural gas, with a Smart Sense control system for efficiency. Best for households that require high hot-water flow across multiple fixtures and prefer a compact unit. It is more complex to install than traditional tank heaters and may require venting and WiFi control components.
FOGATTI Natural Gas Tankless 7.5 GPM
The FOGATTI 7.5 GPM tankless unit delivers up to 170,000 BTU and features a compact design with on-demand heating. It is best for smaller homes or spaces where a full-size tank is impractical. It provides instant hot water and a steady temperature with a four-stage combustion system. A potential limitation is the need for proper venting and gas line sizing to achieve reported flow rates.
Orbek RV Tankless Water Heater
The Orbek RV Tankless Water Heater is designed for RV use and offers 12V DC operation with a remote control. This makes it a strong choice for travelers who need reliable hot water on the road. Best for RV families and campers who want on-demand heat without dedicating space for a traditional tank. A limitation for some setups is the specific RV installation space and dimension requirements.
Buying Guide: Key Purchase Considerations
What type of system are you replacing? If you still rely on a tank, you may prioritize a compact, high-efficiency tankless option or a reliable valve replacement for an aging tank model. For residential homes, consider flow needs and venting requirements. Tankless models deliver continuous hot water but may demand more complex installation and venting. For RVs, compact tankless units and 12V DC options are preferable for space and power limitations.
Does my current gas line and vent support a tankless unit?
Tankless models typically require appropriately sized gas lines and venting designed for their BTU output. Inadequate venting or gas supply can limit performance or create safety concerns. A licensed installer can verify line size, vent routing, and clearance requirements.
What is the right hot water flow for my home?
Evaluate the number of simultaneous hot-water users (showers, sinks, appliances). Tankless systems specify GPM (gallons per minute). Choose a unit with a higher GPM if multiple fixtures run at once. In smaller spaces, a high-efficiency condensing model can provide ample hot water without a tank.
Should I replace valves or the entire heater?
Valve replacements can extend the life of older gas heaters when the tank itself remains serviceable. However, if the heater is old, corroded, or inefficient, replacing with a modern tankless or high-efficiency unit may offer longer-term savings and reliability.
Is professional installation required?
Gas systems typically require professional installation to ensure code compliance and warranty validity. This is especially true for pressure regulators, valve replacements, venting, and gas connections.
Energy efficiency and operating costs
Condensing tankless models tend to offer higher energy efficiency than traditional storage tanks, potentially reducing ongoing energy costs. Look for units with high UEF or comparable efficiency ratings and consider long-term fuel usage.
Frequently Asked Questions
- Can I install a tankless water heater myself? Installation of gas-fired or propane tankless heaters should be performed by a licensed professional to ensure safety and warranty terms.
- What maintenance do tankless heaters require? Periodic flushing to remove mineral buildup, filter checks, and vent inspections are common maintenance tasks.
- Will a valve replacement fix a failing gas heater? A valve replacement can restore proper gas flow control, but it does not fix other potential issues such as heat exchanger corrosion or mineral buildup in older units.
- How do I choose between gas and propane models? Choose based on your fuel source availability and existing connections. Tankless options can operate on either natural gas or propane with appropriate configuration.
- Are there safety concerns with old gas water heaters? Yes. Gas leaks, improper venting, and pilot-burn issues are safety considerations. Professional inspection is advised for older systems.
- What is the advantage of a compact tankless heater for small spaces? Compact tankless units save space and deliver on-demand hot water without a bulky storage tank, ideal for apartments or small homes.