Atwood GC6AA-10E Replacement Guide: Compatible Water Heaters & Installation Tips

The Rundown

For your 2017 Thor Class C with the Atwood GC6AA-10E water heater, finding an exact replacement is impossible since Dometic discontinued this exact model. You'll need to consider compatible alternatives that may require modifications to your existing installation. While both dealers you consulted are partially right about needing modifications, the Suburban is the more accurate recommendation because Dometic acquired Atwood's water heater division but uses different mounting configurations that would require more extensive modifications to your 2017 Thor's cabinet.

The Suburban SW6DE maintains the same 6-gallon capacity and similar dimensions to your failed GC6AA-10E, making it the most straightforward replacement. You're correct that you'll need a door kit - specifically the Suburban 232767 door kit which includes the outer door, inner door, and mounting hardware. The total cost for the water heater and door kit typically runs $450-550 depending on your supplier.

Why It Happens

Tank leaks in Atwood water heaters like your GC6AA-10E typically develop due to a combination of factors common in RV applications. The constant heating and cooling cycles, combined with the steel tank construction, create thermal stress that eventually leads to hairline cracks or pinhole leaks. Your 2017 unit lasting about 6-7 years is actually fairly typical for this model, especially if you've been in areas with hard water or haven't been diligent about anode rod replacement.

The discontinuation of your specific Atwood model stems from Dometic's acquisition of Atwood in 2011 and their subsequent consolidation of product lines. Rather than continue manufacturing the exact same units, they've streamlined their offerings, which is why finding an exact replacement is impossible. The GC6AA-10E was particularly susceptible to tank failures due to its steel tank construction and the way the heating element was integrated into the tank design.

Summer failures are especially common because that's when most RVers are using their water heaters most frequently, putting additional stress on already weakened tank materials. The combination of higher ambient temperatures and increased demand often pushes marginally compromised tanks over the edge into visible leakage.

Gather These Items

• Suburban SW6DE water heater (direct replacement unit, approximately $350-400)
• Suburban 232767 door kit (includes outer door, inner door, gaskets, and mounting hardware, $100-150)
• New water heater bypass kit if your existing valves are corroded (Suburban 161154, $25-35)
• Teflon tape and pipe dope for all threaded connections
• New anode rod (see manufacturer specs for correct part number, $15-20) - comes with unit but good to have spare
• Basic hand tools: adjustable wrenches, screwdrivers, drill with bits
• Propane leak detector solution for testing gas connections
• Wire nuts and electrical tape for 12V connections

The Fix

Start by shutting off your propane supply and disconnecting the 12V power to the water heater at your electrical panel. Turn off the water pump and close the water supply valves to prevent flooding. Drain the existing tank completely by opening the drain plug and pressure relief valve. Disconnect the hot and cold water lines - these should be accessible from inside your RV, typically behind a panel in a nearby cabinet or closet.

Remove the exterior door assembly and carefully disconnect the gas line at the union fitting near the gas valve. Take photos of the gas line routing and electrical connections before disconnection to ensure proper reassembly. The old unit should slide out of the compartment once all connections are removed, though you may need to remove mounting screws from inside the compartment.

Any replacement water heater will likely require significant modifications to mounting systems and connections. Different manufacturers use different mounting configurations, so expect substantial installation work beyond simple replacement. Slide the new water heater into position and secure it properly, then install the new door kit with new gaskets and sealing materials, ensuring proper alignment with your RV's exterior profile.

Reconnect all plumbing connections using new Teflon tape and pipe dope on threaded fittings. The gas connection is critical - use the existing gas line but replace the flare fitting if there's any sign of wear or corrosion. Reconnect the 12V wiring according to your photos, ensuring proper polarity. Before testing, fill the tank completely and check all water connections for leaks, then test the gas connection with leak detector solution before lighting the pilot.

Know Your Limits

While this replacement is within the capabilities of most DIY RV owners, the gas line connection requires careful attention to safety protocols. Check local codes as permits may be required for gas appliance replacement in many jurisdictions. If you're not comfortable working with propane connections or lack experience with flare fittings, hire a certified RV technician for at least the gas portion of the installation. Improper gas connections can result in dangerous leaks or fire hazards.

The electrical connections are straightforward 12V DC work, but if your RV has a more complex control system or you discover unexpected wiring configurations, don't hesitate to consult a professional. Some 2017 Thor models have integrated tank monitoring systems that may require specific connection procedures.

Plan on this being a full day project if you're doing it yourself, including time for multiple leak checks and proper testing. If you encounter significant differences in mounting configurations or discover additional complications like corroded water lines, budget for potential professional assistance. The peace of mind from a proper installation is worth the investment, especially given the safety implications of both water damage and gas leaks in your RV.