Oct 24th 2026
Dometic / Atwood 10 Gallon RV Water Heater Guide: WH-10GEA, GC10A-4E and Parts
MODEL GUIDE · 10 GALLON
Dometic / Atwood 10 Gallon RV Water Heater Guide: WH-10GEA, GC10A-4E and Parts
How to read an Atwood or Dometic 10-gallon model number, the cutout sizes, why there’s no anode, and the parts that fit.
The short version
- Older Atwood: G10, GC10A-4E, GCH10A-4E. Current Dometic: WH-10GEA (and WH-16GEA, 10 gallons actual / 16 “effective”).
- G = gas, C = gas + 110V electric, H = engine heat exchanger, E at the end = electronic ignition.
- Aluminum tank: no anode rod. It drains through a plastic plug (91857).
- Element: 1400 W. The GC10A-4E is rated 10,000 BTU per dometic.com.
Decoding the model number
| Code | Meaning |
|---|---|
| G | Propane gas |
| C | Combination gas and 110V electric |
| H | Engine heat exchanger |
| 10 | Gallons |
| A / AA | Heating element type / version (Atwood’s diagram doesn’t say which letter is which) |
| -3, -4 … | Revision |
| E | Electronic (DSI) ignition |
| P | Pilot relight |
| WH-10GEA | Dometic: water heater, 10 gal, Gas, Electric, revision A |
| WH-16GEA / XT | 10-gallon tank with a mixing valve for 16 gallons “effective” |
From the Atwood service manual and Dometic installation manual.
Cutout and size
| Model | Cutout (H × W × D) | Source |
|---|---|---|
| Older Atwood 10 gal (GC10A etc.) | 15-3/4 × 16-1/4 × 20-5/8 in. | Atwood installation manual |
| XT 10 gal | 15-3/4 × 16-1/4 × 21-3/4 in. | Dometic XT manual |
| WH-10GEA | 15.8 × 16.3 × 20.6 in. | Dometic 2022 manual |
| WH-16GEA | 15.8 × 16.3 × 25.1 in. | Dometic 2022 manual |
Dometic’s legacy product pages list slightly different figures (15-1/2 × 16 × 20-3/4 in.). Measure your opening before ordering a heater or door.
No anode, plastic drain plug
Atwood tanks are aluminum with a zinc-aluminum cladding inside. Atwood says the tank itself acts as the anode, and Dometic says not to install an anode rod. Drain at least once a year through the 1/2 in. NPT drain plug; about 2 quarts stay in the tank, which Dometic says won’t harm it if it freezes.
Common 10-gallon parts
| Part | Number |
|---|---|
| Thermostat/ECO (DSI, front mount) | 91447 |
| Thermal cut-off (one-shot 190°F) | 93866 |
| 110V thermostat/ECO | 91873 |
| Element (1400 W) | 92097 (Atwood lists 92249 element & gasket) |
| Electrode / spark probe | 93868 |
| Element relay | 93849 |
| Drain plug | 91857 |
| P/T relief valve | 91604 (1/2 in.) or 90028 (3/4 in.) |
| Access door, 10 gal | 91385 (older) / 95500–95505 (WH-10GEA) |
From Atwood’s parts lists and our catalog. Burner numbers vary by model and ignition type; send us your model.
Parts for this repair
Dometic 91447 Front Mount ECO/Thermostat Kit (DSI)View part →
Dometic/Atwood 93866 Thermal Cut-Off KitView part →
Dometic/Atwood 91873 Thermostat/ECO, 110V ACView part →
Dometic/Atwood 92097 AC Heating Element (1400 W)View part →
Dometic/Atwood 93868 Electrode (Spark Probe)View part →
Dometic/Atwood 91857 Drain Plug, 1/2 in. NPT (2 pack)View part →
Dometic/Atwood 91604 P/T Relief Valve, 1/2 in. NPTView part →
Dometic/Atwood 91385 Access Door, 10 Gallon (white)View part →
Dometic 95500 / 95505 Access Door, 10 Gallon (WH-10GEA)View part →Shop by category: Dometic part finder, Atwood parts by model, 10 gallon water heaters.
FAQ
What does GC10A-4E mean?
G = gas, C = combination gas and 110V electric, 10 = gallons, A = element type/version, -4 = revision, E = electronic ignition.
Does a Dometic 10 gallon water heater have an anode rod?
No. The aluminum tank doesn’t use one, and Dometic says not to install one.
What is the cutout for a Dometic WH-10GEA?
Dometic’s 2022 manual lists 15.8 in. high × 16.3 in. wide × 20.6 in. deep.
Can I put a Suburban 10 gallon in an Atwood opening?
The Suburban 10-gallon needs a 16-3/8 in. square opening, so an Atwood 10-gallon opening must be enlarged by about 5/8 in. in height.
Not sure which part fits? Contact us with your model and serial number from the data plate and we’ll confirm it before you order.
From the Atwood water heater service manual, Atwood/Dometic installation and operating manuals (MPD 93755/93756, Dometic 94035 and 3317866) and dometic.com.