Marathon 20-Gallon Water Heaters
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No Marathon 20 gallon water heaters in our catalog
Marathon doesn't currently ship any 20-gallon water heaters we track. Try one of the alternatives below.
Marathon 20-Gallon Water Heaters: buyer's guide
Marathon doesn't currently ship any 20-gallon water heaters in the lineup we track. If you're shopping for 20-gallon water heaters, see the full 20 Gallon category for cross-brand options.
About Marathon
Marathon (Rheem) — subsidiary of Rheem. Specialty water-heater manufacturer serving the US market.
For the complete Marathon lineup across all sub-types and capacities, see the Marathon Water Heaters hub.
Other 20 Gallon water heaters brands
If you're cross-shopping 20 gallon water heaters beyond Marathon, the following brands also ship in this category:
About 20-Gallon Water Heaters water heaters
The 20-gallon water heater is the upper-tier point-of-use size — sized for single-occupant ADUs, pool houses, RV park-models, small cabins, and tiny homes. The 20G supports a full normal shower (5–7 minutes at 2 GPM) plus 1–2 hand-washes before recovery — adequate for 1-occupant whole-bathroom service.
- Rheem Performance 20G Point-of-Use Electric (XE20P06PU20U0) — 6-year warranty, 240V, 30 GPH FHD.
- Single-occupant ADUs / mother-in-law suites / garage apartments
- Pool house bathrooms with daily use
- RV park-model trailers
- Small cabins in mild climates
- Tiny homes with 1–2 occupants
For the complete 20 gallon buyer's guide (all brands, full comparison framework), see the 20-Gallon Water Heaters category hub.
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