What You Should Know about Tankless Water Heaters - Wisler Plumbing, Heating, Cooling, & Electrical

Tankless water heaters are drastically different from tank water heaters in terms of how they work. As long as they are installed correctly and sized properly, they will do a great job. There are, however, a few important things everyone should know.

First, a tankless water heater isn’t an instant water heater. What that means is it won’t give you hot water the instant you turn on a faucet. It is more accurately called an on-demand water heater because it only heats the water that you use. It’s able to do so by using a flow sensor, which detects when water begins to flow after you turn on the faucet. It also measures the incoming water temperature and compares it to the temperature that you set the heater. By taking those three parameters (the flow, incoming water temperature, and desired water temperature), the heater is able to determine how to heat the water to produce the desired end result.

The flow rate on a tankless unit can be limited, depending on the BTU or size of the heater. However, most tankless water heaters that we install in our area will deliver 5 1/2 gallons of water at 120 degrees. Another important thing to consider is that different areas will have different incoming water temperatures. A tankless water heater may provide more hot water in Florida than it would further up north, where colder water is coming into the system.

It’s also important to understand that when you turn the faucet off, the water heater stops heating the water. So when you turn the faucet back on, it will take about 3 seconds for it to get back up to speed. Therefore, there will be a short time after turning a fixture on and off when the water will be lukewarm. You may have slightly inconsistent water temperatures at the faucet, which could be frustrating. (That’s why it’s important to understand that an on-demand type of heater only heats the water you’re using.)

If you’re wondering whether a tankless or tank water heater would work best in your home, the team at Wisler Plumbing and Air can make an evaluation and go over your options. For more information, reach out by contacting us online or giving us a call at 540-483-9382.