Best Continuous Hot Water Systems for Homes, Outdoors, and Commercial Use
The best continuous hot water system depends on where you need hot water and how much you use at once. For whole-home supply, the Rheem indoor condensing model is suited to large households, while the outdoor Rheem model avoids indoor venting. The CAMPLUX is designed for portable outdoor showers, and the VEVOR and Ready Hot systems provide hot water at a beverage station or kitchen sink—not throughout an entire home.
| System | Best For | Key Detail |
|---|---|---|
| Rheem RTGH indoor | Large homes | 8.4 GPM; condensing design |
| Rheem RTG outdoor | Homes with outdoor installation space | 8.4 GPM; no venting required |
| CAMPLUX AY132G | Camping and off-grid showers | Portable propane; 1.32 GPM |
| VEVOR 10L boiler | Office and food-service drinks | Up to 50 liters per hour |
| Ready Hot RH-200 | Near-boiling water at the sink | Under-sink tank and faucet |
Rheem RTGH Indoor Condensing Tankless Heater
Best for: Large households that need on-demand hot water for multiple bathrooms. This natural gas system is rated at 8.4 gallons per minute at a 35°F temperature rise and produces 157,000 BTU per hour. Rheem describes it as suitable for three to four simultaneous showers.
The condensing design has a listed Uniform Energy Factor (UEF) of 0.93. It is intended for indoor installation with direct venting, so it may suit homes where an indoor equipment location and vent route are available. It was selected for whole-house use and its stated flow capacity.
Consideration: This is an indoor direct-vent model, so it is not the choice for buyers who need an outdoor installation or a portable system. Actual hot-water flow depends on the temperature rise and demand.
Rheem RTG Outdoor Non-Condensing Heater
Best for: Households seeking whole-home hot water with an outdoor unit location. This natural gas model is rated for 8.4 GPM at a 35°F rise, with 180,000 BTU per hour of output. The product information identifies it as suitable for three to four simultaneous showers.
The non-condensing design eliminates the need for venting through the home, and the unit has a metal cabinet and supports wall mounting by a qualified installer. Its 0.82 UEF is listed by the manufacturer. It was selected as the outdoor-installation alternative to the indoor Rheem model.
Consideration: Choose this model only if outdoor installation suits the property and local installation requirements. Its listed UEF is lower than the indoor condensing Rheem’s, and it is not a portable or point-of-use appliance.
CAMPLUX AY132G Portable Propane Water Heater
Best for: Campers, RV users, and off-grid users who want an outdoor shower. The portable propane heater supplies 1.32 GPM of on-demand hot water and uses temperature and water-flow dials. It weighs 10 pounds, has a folding handle, and runs on two D-size batteries rather than household electricity.
The stated minimum starting water pressure is 3.0 PSI, a useful specification for some remote water setups. It was selected for mobility and outdoor use rather than whole-house capacity.
Consideration: Its 1.32 GPM output is much lower than the Rheem whole-home models, so it is not intended to supply several household fixtures at once. It is an outdoor-use product; plan for an appropriate water source and propane setup.
VEVOR 10L Commercial Electric Water Boiler
Best for: Offices, beverage stations, and food-service settings that need repeated hot-water draws. VEVOR lists up to 50 liters per hour of output and a 10-liter capacity. Its adjustable temperature range is 104°F to 201°F, shown on an LED display.
The 1,500-watt unit uses a 316 stainless steel heating element and automatically refills and reheats when connected to a water supply. It was selected for high-volume beverage service, not residential bathing.
Consideration: This is a countertop-style commercial water boiler, not a whole-home water heater. Its performance depends on a suitable water connection and electrical setup; verify both before choosing it.
Ready Hot Manual Dial Instant Hot Water Dispenser
Best for: Kitchens where near-boiling water is needed at the sink for drinks or cooking. The Ready Hot system includes a brushed-nickel hot-and-cold faucet and a 2.5-quart, 1,300-watt stainless steel tank. Its manual control adjusts hot-water temperature from 140°F to 200°F, and the manufacturer lists output of over 60 cups per hour.
The tank sits under the sink, while the faucet requires a 1⅜-inch mounting hole. It was selected as a practical point-of-use option for fast access to hot water.
Consideration: The small tank serves a sink faucet, not showers or multiple household fixtures. Check the mounting space and faucet-hole requirements before installation.
Buying Guide: How to Choose a Continuous Hot Water System
Do you need hot water for the whole house or one location?
Start with the intended use. Whole-house gas tankless heaters are designed to supply plumbing fixtures, while the Ready Hot dispenser serves a kitchen sink and the VEVOR boiler serves beverage needs. The CAMPLUX is for portable outdoor showers. Comparing these products by flow rate alone can be misleading because they serve different purposes.
How much hot water will you use at once?
For a household, consider simultaneous showers and other fixtures, not just the number of people. The Rheem models list 8.4 GPM at a 35°F rise, but the stated flow is tied to that temperature rise. For beverage service, compare the VEVOR’s hourly output and temperature range. For camping, consider whether 1.32 GPM meets your shower needs.
Where can the system be installed?
An indoor gas unit needs an appropriate direct-vent installation. The outdoor Rheem model avoids venting through the home but requires a suitable exterior location. Portable propane and electric point-of-use appliances have different placement, fuel, water, and electrical needs. Review product instructions and local requirements before installation.
Which energy source and controls fit your setup?
The Rheem models use natural gas; the CAMPLUX uses propane and batteries; the VEVOR and Ready Hot units are electric. Also compare controls: the portable heater uses flow and temperature dials, the VEVOR has digital temperature control, and the Ready Hot uses a manual dial.
Frequently Asked Questions
What does continuous hot water mean?
It generally describes a system that heats water on demand or maintains ready-to-use hot water, rather than relying only on a finite storage tank. Output is still limited by the system’s capacity and the amount of simultaneous demand.
Which system is best for a large family?
The Rheem whole-house models are the relevant options in this selection. Compare indoor versus outdoor installation, stated flow at a 35°F rise, and the number of fixtures likely to run at once.
Can a point-of-use dispenser replace a whole-house heater?
No. The Ready Hot is designed for a sink, and the VEVOR is designed for beverage service. Neither is presented as a system for supplying household showers and bathrooms.
Is a portable tankless heater suitable for camping?
The CAMPLUX is designed for outdoor and off-grid use, with propane operation, battery power, and a portable 10-pound design. Its stated flow is 1.32 GPM, so compare that capacity with your intended use.