How to Choose the Right Compact Tankless Water Heater
Tankless Water Heaters have seen huge increases in unit sales over the last 5 years. Many manufacturers are seeing their yearly sales grow by 100% or more and it is estimated that within the next 5 to 10 years more than 50% of all American homes will have Tankless Water Heaters.
The reason for the huge popularity in Tankless Water Heaters, also called “On Demand” Water Heaters, is because, with them, there is no need for long wait times for water to “warm up” when you turn on the hot water. These compact units mount on a wall either inside or outside of the house and supply hot water on demand for as long as you need it.
There is no longer a need for huge water heater tanks that take up needed space and gallons of wasted water, waiting for it to heat up before you can start using it, there is also no need to keep heating water when you don’t even need it.
Tankless Water Heaters come in a variety of sizes and capacities, so how do you find the size that is right for your needs? This article will explain what you need to consider when choosing the Compact Tankless Water Heater that is right for your needs.
Determine the Flow Rate You Require
First you need to figure out the total number of devices you want to run and their total flow rate. Then, add up their gallons per minute (gpm) flow rate. This will equal the desired flow rate you will want the water heater to produce.
For instance, say you expect to run a hot water faucet with a flow rate of 0.75 gpm and a shower with a flow rate of 2.6 gpm. The flow rate through the compact water heater would have to be at least 3.26 gpm. To reduce the flow rate, install low-flow water fixtures like Moen’s WaterSense faucets.
Determine the Required Temperature Rise Needed
Unless you know the exact temperature of the incoming water, assume that it is 50°F. Using a low temperature assumption will ensure you don’t undersize your tankless water heater, if you live in a warm climate your water temperature will most likely be much higher.
For most uses, you will want your water to be heated to around 105-115°. Since your assumed incoming water temperature is 50°F, you will need a water heater that produces a temperature rise of 55°F.
Choosing the Right Size
You will need a tankless water heater that can produce at least a 60 degree rise in temperature at 5.2 gallons per minute.