Best Water Heater for a Small Apartment or Condo
Space is the constraint: apartment installs need compact dimensions, quiet operation, and often a 120 V circuit. Compact heat pump units and small-tank models dominate this use case; check the height and diameter specs against your closet before anything else.
Sizing target: cover one shower, one sink — never both — a first-hour rating of at least 35 gallons for a tank, or 2 GPM sustained winter flow for a tankless. Every model below is ENERGY STAR certified; rankings use efficiency and estimated running cost only.
Best heat pump water heaters
Filtered to first-hour ratings of 35 gallons or more, then ranked by efficiency.
| Model | UEF | Capacity | Est. cost/yr |
|---|---|---|---|
| GE Profile Heat Pump 50-Gallon (PH50S10BNY01) | 4.5 | 75 gal first hour | $187 |
| GE Profile Heat Pump 80-Gallon (PH80S10BNY01) | 4.5 | 101 gal first hour | $187 |
| GE Profile Heat Pump 80-Gallon (PH80S10BPY01) | 4.4 | 101 gal first hour | $192 |
| Bradford White RE2HP65-1NCTT 65-Gallon | 4.2 | 82 gal first hour | $201 |
| LG APHWC502D 50-Gallon | 4.2 | 81 gal first hour | $201 |
| LG APHWC502L 50-Gallon | 4.2 | 81 gal first hour | $201 |
| LG APHWC502M 50-Gallon | 4.2 | 81 gal first hour | $201 |
| Friedrich Heat Pump 80-Gallon (PROH80 T2 FD400-30) | 4.07 | 87 gal first hour | $206 |
Best gas tankless water heaters
Filtered to models sustaining at least 2 GPM at a 70 °F winter temperature rise, then ranked by efficiency.
| Model | UEF | Capacity | Est. cost/yr |
|---|---|---|---|
| Bradford White RTGR150N1 | 0.98 | 4.2 GPM @ 70 °F rise | $251 |
| Bradford White RTGS150N1 | 0.98 | 4.2 GPM @ 70 °F rise | $251 |
| Noritz EZ111DV (GQ-C3261WX-FF-1 US) | 0.98 | 5.5 GPM @ 70 °F rise | $251 |
| Noritz EZ111DV (GQ-C3261WX-FF US) | 0.98 | 5.5 GPM @ 70 °F rise | $251 |
| Noritz EZ71DV (GQ-C2661WX-FF-1 US) | 0.98 | 4.5 GPM @ 70 °F rise | $251 |
| Rinnai CX199I REU-NB3237FFC-US | 0.98 | 5.6 GPM @ 70 °F rise | $251 |
| Rinnai CXP199I REU-NBP3237FFC-US | 0.98 | 5.6 GPM @ 70 °F rise | $251 |
| Rinnai RX180I REU-NB2934FF-US | 0.98 | 5 GPM @ 70 °F rise | $251 |
Best gas storage water heaters
Filtered by first-hour rating (or DOE draw-pattern rating where unavailable), then ranked by efficiency.
| Model | UEF | Capacity | Est. cost/yr |
|---|---|---|---|
| A. O. Smith GC6-PS4050-V 1 40-Gallon | 0.9 | 86 gal first hour | $273 |
| A. O. Smith GC6-PS5065-V 1 50-Gallon | 0.9 | 118 gal first hour | $273 |
| A. O. Smith GPCC-40L 1 40-Gallon | 0.9 | 86 gal first hour | $273 |
| American GPCT-40L 1 40-Gallon | 0.9 | 86 gal first hour | $273 |
| American GPCX-50L 1 50-Gallon | 0.9 | 118 gal first hour | $273 |
| American GSP-100 2 30-Gallon | 0.9 | 170 gal first hour | $273 |
| Envirosense Reliance Home Comfort ENV-40N-RHC 1 40-Gallon | 0.9 | 86 gal first hour | $273 |
| Envirosense Reliance Home Comfort ENV-50N-RHC 1 50-Gallon | 0.9 | 118 gal first hour | $273 |
Frequently asked questions
What size water heater does a small apartment or condo need?
Plan for the peak hour — one shower, one sink — never both. For a tank that means a first-hour rating of at least 35 gallons; for a tankless, sustained flow of about 2 GPM at a winter temperature rise.
Is a tank or tankless water heater better for a small apartment or condo?
Both work if sized correctly. A tank rides out simultaneous use from storage but can run out; a tankless never runs out but caps how much can run at once. With 1 bathroom, the deciding factors are usually fuel available, installation cost, and running cost — heat pump models are the cheapest to run in most of the US.
How are these recommendations ranked?
Purely from certified ENERGY STAR data: models that meet the household's capacity threshold, ranked by Uniform Energy Factor with estimated annual running cost as the tiebreaker. No prices or sponsorships are involved.