Tankless and Conventional Water Heaters

Tankless Water Heaters

Tankless water heaters, sometimes known as instantaneous, continuous flow, inline water heaters, are the perfect alternative to conventional tank heaters.

Tankless water heaters heat water on demand or instantly rather than keeping hot water in reserve like conventional tank heaters. Tankless water heaters use less energy than tank heaters which in turns means lower energy bills for you.

Tankless water heaters can be operated electrically or with natural gas or propane. Gas tankless water heaters can heat more water faster while electric tankless water heaters need access to a lot of electric power to rapidly heat water.

Tankless water heaters are very efficient when it comes to energy conservative. Tankless water heaters have efficiency ratings at nearly 99%.

Most tankless water heaters supply hot water for the whole house including appliances. The tankless water heaters that supply hot water for the whole house are largest of the tankless water heaters. Point-of- use tankless water heaters are smaller units and can be placed under sinks or other easy access areas.

Point-of-use tankless water heater units provide hot water for a specific outlet versus the whole house. Point-of-use tankless water heaters are located right where the water is being used and save more energy than centrally installed tankless water heaters, but are usually used in combination with a central water heater because of their small tank size.

Generally speaking, tankless water heaters are good choices because they don’t take up much space and can be hidden out of site. So, you won’t have to worry about people looking at it.

Here are a few reasons why you should look into tankless water heaters…

Unlimited hot water

As water is heated while passing through the system an unlimited supply of hot water is available with a tankless water heater however, this can also be a disadvantage as running out of hot water self-limits use while a tankless heater has no such limit.

Size

Tankless water heaters can be mounted under a sink, in an easy access area, or anywhere else you think would be a good location. Because there is no tank, the places of where it can go are virtually endless.

Water damage is minimized

Tankless water heaters have no tanks to store water, so there are no chances of water damage do to a leak or hole in the tank. There are still risks of water damage from faulty parts such as improper piping or bad fittings.

Longevity

Tankless water heaters haven no tanks meaning tankless water heaters will outlast the conventional water heater twice as many years because corrosion is due to standing water in the tank. The corrosion on the tankless water heater will be on the pipes or around the fittings vs. the tank.

Environmentally Friendly

Tankless heaters are designed to only use gas and water when they are being used. Therefore, you are not wasting resources to heat the water in a conventional water heater.

Conventional Water Heaters

What is the average lifetime of a gas water heater?

The average lifetime of gas water heater is 9 years. The range is 5-14 years.

How is FHR and Therms used to compare the efficiency of water heaters?

The first hour rating (FHR) tells you the number of gallons per hour of hot water. Therms relate to the gas consumption of water heater. When you are shopping for hot water heater, compare the energy factor on the energy guide label. FHR and Therms are not sufficient to calculate the energy factor. Also remember to compare water heaters of equal capacity and FHR.

What efficiency standard does a dual use residential water heater need to meet as a water heater or a boiler (used for both potable water and space heating purposes)?

For a dual unit, it must meet the efficiency standard requirements of both applications. Your local building department may have additional requirements for such units.

What is a hot water recirculating system?

A "hot water re-circulating" system usually refers to a domestic hot water system that circulates the heated water through the house continuously so as to eliminate or shorten the delay in hot water reaching the faucet after the user turns it on. These systems are most common in multifamily or large building applications where otherwise the delays would be truly unacceptable. They can be real energy hogs if the pipes aren't well insulated.

How do I choose the best electric or gas tankless water heater for my home (2300 sq. ft.)?

Sizing of hot water heaters should be based on the number of occupants and their peak hour water demand and not on the size of the house.

Are tankless water heaters more efficient?

Tankless water heater efficiencies are not addressed by the Federal standards. Check the EREC fact sheet at http://www.eren.doe.gov/consumerinfo/refbriefs/bc1.html for additional resources.