Tankless Buying Guide
Rheem offers the best water heaters in the business, but to enjoy endless hot water, it’s important to choose the right one. To find the best tankless gas water heater or tankless electric water heater for your home, follow these four easy steps:
- UNDERSTAND YOUR OPTIONS
There are two basic types of tankless water heaters: gas (including both natural gas and propane (LP)) and electric (which comes in both whole-home and point-of-use configurations). Gas tankless water heaters are less expensive to operate, but they typically require venting—outdoor models are the notable exception. Electric tankless water heaters don’t require venting, and because they usually only require a dedicated electrical circuit, they’re easier to install. What may ultimately help make the decision is where you need the hot water:
- For a single location—like a sink, bathroom, garage or workshop—choose a point-of-use tankless electric water heater.
- For whole-home applications, choose the water heater type that matches your home service, either electric, natural gas or liquid propane.
- CALCULATE THE TEMPERATURE DEGREE RISE BASED ON YOUR LOCATION
Because average water supply inlet temperature varies by location, the ideal tankless water heater in the south might not work at all in the north. And a tankless gas water heater might work great at 8,000 ft. altitude, but not work at all at 12,000 ft.
The degree rise for your area is the difference between the inlet temperature and your desired set temperature (105°-60°=45°).
- ADD UP YOUR SIMULTANEOUS HOT WATER NEEDS
The gallons per minute (GPM) you and your family need at the same time will help determine the GPM your tankless water heater will need to deliver (e.g. For two showers and a load of laundry, you’ll need a water heater that’s rated to deliver at least 5.5 GPM for your area (2.0+2.0+1.5=5.5)).
| Appliance |
Typical Gallons Per Minute |
| Standard Hand Sink |
0.5 |
| Bath Tub |
4 |
| Water-Saver Shower Head |
1.5 |
| Standard Shower Head |
2.0 |
| Kitchen Sink |
1 to 2 |
| Washing Machine |
1 to 1.5 |
| Dishwasher |
1 to 2 |
| Whole Home |
up to 6 |
- CHECK THE SPECS
The product information page or spec sheet (downloadable on product information pages under Documents) for each of our tankless water heaters lists the gallons per minute at certain degree rises.
- On the GPM chart, find the line with your degree rise from step 2. It will tell you how many GPM the water heater will deliver at that degree rise.
- Take the total GPM you need from step 3 and compare it to the one from the chart.
- CONSIDER UNIQUE FEATURES AND BENEFITS
Some features are so unique that they’re limited to certain models.
- If you want instant hot water at the faucet, consider a Rheem tankless water heater with recirculation.
- If you want to free up even more space inside your home, consider a Rheem outdoor tankless water heater.
- To enjoy WiFi control, which enables you to adjust your water temperature and monitor your system from anywhere in the world, consider a model that’s EcoNet Enabled.
Tank or Tankless?
Still deciding whether or not a tankless water heater is right for you? Watch this video:
Why Tankless?
The Basics
Tankless water heaters are more energy efficient than most conventional tank-type water heaters, because they provide hot water on demand at the precise temperature needed, so there is no storage and therefore no need to expend energy heating that stored water. About the size of a medicine cabinet, these space-saving, compact models can easily be wall-mounted indoors and even outdoors, depending on the climate.
Continuous Hot Water, Continuous Savings
Rheem tankless water heaters combine innovative technology and functionality for a hot water solution that can supply a continuous flow of low-cost hot water whenever and wherever you need it. No matter how many body sprays and showerheads, no matter how deep the whirlpool, you will not run out of hot water with a properly sized tankless water heating system.
Tankless Water Heater FAQs
Still have questions about going tankless? As the global leader in tankless water heaters, we likely already have the answer to your question in our ever-growing tankless FAQs section.
