Tankless Electric Water Heater

The most obvious difference between gas and electric tankless water heaters is the energy source that is used. Gas tankless heaters use either Natural Gas (NG) or Propane (LPG), but also use electricity (120v) to power an internal fan and other controls. Electric tankless heaters operate using only electricity. Electric tankless water heaters operate at higher energy efficiency, in the case of Hubbell the thermal efficiency is 98%+, compared to gas tankless which ranges from Energy Factor ratings of 0.82 to 0.96 depending upon model. Electric tankless is more efficient in large part because gas tankless models operate by burning gas, which is harder to control than electricity and is less efficient due to heat lost in the flue exhaust. Gas heaters require exhaust and/or fresh air intake venting, whereas electric heaters do not. Please note that efficiency and operating cost are two different things, to determine operating cost one must consider their cost of energy and usage in addition to the operating efficiency of the heater. Gas tankless water heaters cost more to purchase compared to electric tankless heaters. When replacing a storage tank type water heater with a tankless heater, it should be noted that both gas and electric tankless require changes to the existing plumbing and wiring of the tank they are replacing. When installing a new gas tankless heater, most installations will require a new/upgraded venting and gas line. When installing a new electric tankless heater, most installations will require upgraded wiring to the heater and replacement of the circuit breakers in the electrical panel. The largest available residential and light duty commercial gas tankless water heater is 199,000 BTU/Hr, but the most common size has an output of about 123,000 BTU/Hr. After factoring for energy efficiency, this is equivalent to roughly 36 kW. By contrast, the largest residential/light duty commercial electric tankless water heater is 27 kW, which has an effective output of 91,000 BTU/Hr. In terms of operation and maintenance, a gas tankless heater is considerably more complicated to maintain and service compared to electric tankless. In addition, an electric tankless heater will provide more accurate and consistent hot water temperature throughout a full range of flow rates compared to a gas tankless heater. However, gas tankless heaters because they are available in larger BTU sizes can provide a higher hot water flow rate/temperature rise for very large installations compared to a standard electric tankless heater.

This is a common misconception of tankless water heaters. A tankless water heater does heat water on-demand instantly. Just like a tank water heater, it still takes the same amount of time for the hot water to travel through the pipes and flush out the standing water that has cooled down and is already inside the hot water plumbing. No matter what type of heater is installed, it will always take time for the hot water to travel through the plumbing before arriving at the fixture. The length of time it takes always depends on the length of the pipes, the amount of flow through the fixture and the water pressure. In general, a centralized water heater will require the most time to deliver hot water to the fixture, whereas a Point-of-Use water heater will deliver hot water to the fixture in the shortest amount of time.

A storage tank water heater maintains a tank full of hot water 24/7/365 and will heat water even during periods of no usage in order to make up for standby heat loss. A tankless water heater only consumes power (whether its gas or electric) when there is demand for hot water. They take up significantly less space and typically can be located close to the point of use, thus providing more efficient delivery of hot water. Tankless water heaters provide continuous hot water and never run out as long as the heater capacity is not exceeded.

No. Hubbell electric tankless water heaters do not restrict water flow. Other brands may incorporate a flow restrictor device within their tankless heater or require a flow restricting device be installed in the plumbing or fixture itself as a method for controlling temperature. This is not the case for Hubbell electric tankless water heaters.

It depends. Due to the relative small physical size of a tankless water heater compared to a storage tank water heater, a tankless option can be advantageous from a space and weight saving perspective and can sometimes be installed closer to where you want hot water. Tankless water heaters do not store heated water like a storage type water heater; they only heat water as there is demand and therefore must be sized to meet the maximum flow and temperature rise for the application. Therefore, before proceeding with a tankless heater you must carefully understand your application and review your available power. Hubbell offers a wide range of electric tankless marine heaters go to Electric Tankless for details. It is critical that before choosing to go tankless you have carefully considered all of the factors that sometimes make the tankless option more complicated and risky compared to a storage type water heater.

There are numerous ways to purchase a Hubbell water heater depending upon the model you desire and your geographic location. The easiest way is to contact Hubbell directly at 800-647-3165 and ask for the sales department where you will be directed to either our local representative or our order entry department for quick and easy ordering.

Parts are available for your Hubbell water heater direct from the factory. Please call 800-647-3165 and ask for our parts department. Please have your model and serial number handy.

Hubbell has more than 35 product families available in over 4,000,000 configurations. There are numerous features, configurations and ratings we provide but for practical reasons are are not listed in the sales brochure. If you have a specific requirement and you do not see it in the brochure, please contact a Hubbell Sales Engineer...chances are we have what you need.

Legionella is the bacteria responsible for Legionnaire’s Disease, an acute bacterial infection of the lower respiratory tract. This bacterium was first identified in 1977 by the Centers for Disease Control as the cause of an outbreak of pneumonia that caused 34 deaths at a 1976 American Legion Convention in Philadelphia. Pontiac Fever is a less severe, non-pneumonia, flu-like disease that is associated with and likely caused by Legionella bacteria. Legionella is a fairly common water bacterium and has been found to exist widely in many surface water sources including lakes, rivers, streams and ponds. It can also be found in ground water sources and some soils. At the levels found in these naturally occurring sources it typically does not pose a threat to public health. When the bacterium enters a domestic water system it can find an ideal host environment of warm water temperatures (105-115°F), stagnant water areas (isolated storage tanks and dead-end piping legs) and ample food sources (sediment, scale, deposits and biofilm). Under these conditions Legionella can rapidly colonize, forming higher concentrations that can pose the public health threat of Legionnaire’s Disease. There are many methods of controlling colonization of Legionella bacteria. However, a widely accepted and preferred method is to maintain the hot water system storage temperature continually at or above 140°F. Unfortunately, the elevated temperature necessary to minimize the growth of and kill Legionella bacteria has the potential to cause serious thermal shock and scalding injuries. As such, many plumbing engineers will specify that the water heater be set to maintain water temperatures at 140°F or higher to reduce the risk of Legionella, but then specify the appropriate mixing valve to ensure safe delivery of hot water to the fixtures. For a more thorough discussion of Legionella please go to here and the following link to the US Department of Labor OSHA information regarding Legionnaires’ Disease OSHA here

Check out the Hubbell Product Center at Here for a complete listing of all technical documentation available by model. Get easy access to Installation, Operation & Maintenance manuals, Sales Brochures, Service Bulletins, Wiring Schematics, Parts Breakdowns and various other technical documents related to the full line of Hubbell water heaters. Or, if you prefer, please call us at 800-647-3165 and ask to speak to a Sales Engineer.

Parts are available for your Hubbell water heater direct from the factory. Please call 800-647-3165 and ask for our parts department. Please have your model and serial number handy.