Is a tankless water heater a good option for your home?

The installation of tankless water heaters in residences is becoming more and more popular as many people are beginning to see the advantages of tankless water heaters over the more familiar water heaters with a tank. As you know, when you own a water heater with a tank, you have to accommodate a large vessel somewhere in your home that holds and heats 40 to 50 gallons of water whether hot water is being used or not.

The water in the reservoir tank is stored at a pre-set temperature and when it cools below that temperature, the water heater reheats the water to the pre-set temperature whether you are using it or not. This causes your home to use more gas or electricity to bring the water back up to temperature.

The advantage of a tankless water heater is that no water is stored so nothing is being kept hot unless someone is actually calling for hot water by using a faucet. With a tankless water heater, you eliminate the need for storage of a large appliance, and only when you turn on the faucet for hot water, does the gas or electric tankless heater fire up. Tankless is more efficient by not wasting energy or your money.

St Paul Pipeworks plumbers do not recommend buying a tankless water heater from either a big box store or online because homeowners usually do not know what the correct sizing should be for their homes. When people look online and see reviews saying tankless water heaters do not work, often it is because the tankless heater either was improperly sized or the unit was improperly piped.

A licensed plumber will help you with the correct sizing and install the correct piping so that your heater will work correctly for your home. There are different parts of the country where the cold water is not coming in as cold as it is here in Minnesota, so manufacturers offer three different British Thermal Unit (BTU) sizes of tankless water heaters.

One obvious issue with a tankless water heater is that when you don’t have a storage tank, you have a very small amount of hot water in the pipes being heated at any given time. You have to have a much higher flame or electricity to heat the water as it is traveling through a small coil of pipe inside of the water heater. The coil runs back and forth inside of the unit and the water is heated as it travels through the coil. For example, a gas water heater with a tank uses approximately 40,000 BTUs when it is running.

A gas tankless water heater in our part of the country, where the water comes in a little colder, needs 200,000 BTUs to heat the water. However, the tankless water heater only uses energy while a faucet is running. Once you turn the faucet off, the heating unit turns off as well. The unit uses less energy overall than a tank water heater. Tankless water heaters tend to be more expensive to purchase and slightly more expensive to install, especially the ones that use gas because they require larger gas pipes or increased gas pressure than water heaters with a tank.

Tankless water heaters last about twice as long as water heaters with a tank. The guarantee on most of the tank water heaters is six years and most of those last for about 12 to 14 years. Most tankless water heaters have a 15 to 20-year guarantee on the heat exchanger, or equivalent of the tank.

In a tankless water heater, you will have continuous hot water as long as the faucet is turned on. Though not recommended you could leave that faucet on for a week and still get hot water.

St Paul Pipeworks plumbers recently installed two tankless water heaters in a birthing center, which is a high volume setting. There are multiple birthing suites that each contain very large soaking tubs and multiple showers. This birthing center kept running out of hot water with their regular tank water heaters. After interviewing birth center employees, St Paul Pipeworks plumbers went in with a technical expert and sized the new tankless water heaters and installed a system in where they will never run out of hot water. For a family of four, one tankless water heater is large enough to allow use of three sources of hot water at the same time and never run out of hot water.

If you are interested in installing a new tankless water heater in your home or are looking for a quality plumber in the St. Paul and Minneapolis metro area, give St Paul Pipeworks a call today.


Yours Truly,

Matthew Dettwiler

Social Media Manager


Tankless Water Heaters: Are they right for me? Ask A Plumber