best tankless gas water heater reviews of 2023

1.Temperature rise

Temperature rise is the difference between the temperature of the incoming water and the hot water delivered by the tankless water heater. For example, if you reside in a region having groundwater temperature as 60 degrees Fahrenheit and your required hot water temperature is 120 degrees Fahrenheit, the heater should be able to increase the incoming water temperature by 60 degrees Fahrenheit.

The lower the water temperature, the less GPM your tankless water heater produces as it will be struggling to raise the temperature of the water.

The temperature rise is an essential factor to consider when selecting tankless water heaters, as it can affect the performance and efficiency of the unit. The lower the temperature rise of the water, the more heat energy is required for heating water, which can result in increased energy consumption and costs.

2.Power input (BTUs):

The power input (measured in BTU) of gas heaters can vary depending on the specific model and size. As a general rule of thumb, a tankless gas heater with a power input of around 199,000 BTU can effectively provide hot water for a family of four and usage of two to three bathrooms.

When determining the appropriate BTU requirement for a house, various factors such as the number of people living in the household, the type and size of the fixtures, and the climate should be considered. However, as a general guide, here is a breakdown of BTU requirements for a house based on the number of bathrooms:

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• 1 Bathroom: 100,000 – 150,000 BTU
• 2 Bathrooms: 150,000 – 199,000 BTU
• 3 Bathrooms: 199,000 – 250,000 BTU
• 4 Bathrooms: 250,000 – 299,000 BTU

3.Size:

Tankless water heaters come in a range of sizes, and it’s important to choose one that is appropriately sized for your household. A unit that is too small will not be able to keep up with demand, while a unit that is too large will be less efficient and more expensive to operate.

4.Fuel type:

Tankless water heaters can be powered by electricity, natural gas, or propane. Each fuel type has its own pros and cons, so you should consider which one is most suitable for your home and budget.

Natural gas: natural gas tankless units are generally the most cost-effective option, as natural gas is available in gas line and typically less expensive than electricity. They are also relatively efficient compared to their electric tankless water heater counterparts, with some models having energy efficiency ratings as high as 98%.

Propane: Tankless water heaters that run on propane are a good choice for areas where natural gas is not available. They are generally more expensive to operate than natural gas models, but still more cost-effective than electric tankless water heaters.

5.Energy Efficiency:

Look for a tankless water heater that has a high energy factor (EF) rating, as this will indicate how efficiently the unit converts fuel into heat.

Warranty: Make sure to choose a tankless water heater that comes with a good warranty, as this will provide you with protection in case anything goes wrong with the unit.

6.Price:

Best Tankless gas water heaters can vary from $300 to $2500 in price, so it’s important to set a budget and look for a unit that fits within it.

7.Flow rate:

The flow rate of a water heater refers to the amount of water that the heater can heat and deliver to a plumbing fixture, such as a showerhead or faucet, in a given amount of time. It is usually measured in gallons per minute (GPM).

For example, if a water heater has a flow rate of 4 GPM and you are using a showerhead that has a flow rate of 2.5 GPM, the water heater will be able to fully heat the water for the shower. However, if you were using a showerhead with a flow rate of 5 GPM, the water heater would not be able to fully heat all the water, and you would experience a decrease in the temperature of the water as you shower.

The flow rate of a water heater can be affected by a variety of factors, such as the size of the heater, the type of fuel it uses, and the efficiency of the heating element. In general, larger water heaters and those with more efficient heating elements will have higher flow rates.

8.Indoor and outdoor gas tankless heaters

Like tank style water heaters, outdoor tankless gas water heaters are installed outside of the building. They are typically made of stainless steel or other weather-resistant materials to withstand harsh weather conditions such as rain, heat, and cold temperatures. They have their own venting system, which can be more complex and expensive than indoor units.

Outdoor units are best for homes or buildings that don’t have enough indoor space to accommodate an indoor unit or if you do not want to bring inside a gas line. Whereas, this is not the case with electric water heater.

Indoor tankless gas water heaters are typically installed inside a home or building, such as in a utility room, garage, or closet. They are protected from the elements and can be connected to the home’s existing gas and venting systems. Indoor units are typically more energy efficient, as they are not exposed to the harsh weather conditions.

9.condensing and non-condensing tankless models

Condensing and non-condensing tankless heaters are both tankless gas water heaters, but they differ in their operation and efficiency. Also these two variants are not available in electric water heater.

A non-condensing tankless gas heater uses a standard heat exchanger to heat the water, which results in some heat loss through the venting system. This type of tankless gas water heater typically has an energy efficiency rating of around 80%.

Condensing tankless gas water heaters, on the other hand, reuse exhaust gas by capturing the heat (that would usually be lost through the venting system in a non-condensing unit) from the unit’s exhaust gases and using it to preheat the incoming cold water. This results in a higher energy efficiency rating, typically around 90%.

Condensing tankless gas water heaters are more efficient than non-condensing units and can save you money on your electricity bills in the long term. However, they can be more expensive to purchase and install.