Best Tankless Water Heater Replacement for Atwood GC10A-4E

Updated 03/20/2026 | Published 03/18/2026

Products Featured in This Question

Furrion RV Tankless Water Heater - 60,000 Btu - 18" x 18" Door

(412)

$815.95

Furrion RV Tankless Water Heater - 60,000 Btu - 18" x 18" Door

(412)

$976.40

Question:

My customer wants me to replace his ANSI GC10a-4e with a tankless unit. I want something that fits pretty close so I do not need to modify much - Suggestions?

asked by: Donny Z

Expert Reply:

Hello again Donny; the best tankless replacement for that GC10A-4E is the Furrion RV Tankless Water Heater # FR68SR (white) or # FR42TD (black). This will fit the existing cutout since it measures 12-5/8" wide x 12-5/8" tall x 19-1/4" deep. It also comes with an 18-1/8" x 18-1/8" door which is specifically sized for replacing the old Atwood 10 gallon models. It is also the most reliable and has the best performance when compared to other tankless models.

expert reply by: Robin H

Furrion RV Tankless Water Heater
(click to enlarge)

Kevin

3/20/2026

Yes. I purchased and installed this furrion unit as a direct replacement to a 10 gallon unit of the same dimensions. The removal and installation of the old and new are straight forward. I did not have to modify the original opening at all. Direct fit. The following are points intended to avoid issues. 1) If like my camper, I needed a short section of 2x4 under the Furrion unit to support it and bring it up to the proper height of the original factory opening. 2) The instructions are accurate. Trust them and are well written. 3) The thermostat control was mounted in close proximity to the original on/off switch so I could wire the 12 volt hot lead to that switch so the thermostat can be shut off completely. Why? Because it will have a .25 amp constant battery draw if you don't shut it down. On shore power - no issue. On battery, the draw adds up. Just be aware that shutting down by this master switch will disable the freeze avoidance feature of the unit. I drain my unit if a hard freeze is expected. 4) After installing my unit, it wouldn't fire up. This unit requires a tightly closed water loop. My problem was an ever so slightly opened winterizing drain valve followed by a slight leak in the outdoor shower faucet. Once discovered and remedied, the unit fired right up. 5) Hard freezes are the enemy to the Furrion. There is a copper heat riser inside the unit. If you don't drain it completely, the copper tube will burst at the bend because the copper is thinner at the bend. Shut off the main cold water to the unit and drain it per the winterizing instructions. Remove the plastic water filter screw (front, black plastic threaded) and also the 1/4 inch brass threaded drain screw below it. Water will flow and stop. Then insert a 1/4 inch piece of tubing into each one a blow out the remaining water in the heat riser. Each in turn. Both are easy access from the front after clip on panels are easily removed. You've been warned. A new heat riser is availble for 150.00 and a day to install if you are handy. Avoid this by the procedure above. 6) I really like this unit. It works better than I expected it to and is reliable. Again, this unit relies on stable water pressure from 7 to 60 lbs in a tight loop. If it won't fire and there is no code on the thermostat, look for a leak in the water input loop. I would buy one again. So much better than the tank heater. I also found the digital error codes helpful and accurate. Misfires are caused by low fuel, low battery or low water pressure. Now you can confidently make your decision. Enjoy! I do....