Choosing a Water Heater to Suit Your Needs

Not so long ago replacing a hot water heater was a no-brainer. Just remove the old tank and install a new tank, like for like. Today plumbers and plumbing contractors can offer current customers a full menu of replacement options from a basic gas or electric storage tank unit through a growing list of “hybrid” heaters. What is happening right now is the beginning of an explosion of new options in water heating for each homeowner. One of the most important attributes of plumbing contractors is “Doing the right thing for their customers”. The progressive plumbing contractor needs to be sure that they are at least exposing their customers to the options available and to the possible energy saving, water saving, and long term money saving available to them if they want there customers to be truly satisfied.

Options include standard minimum efficiency storage tank heaters, Energy Star storage tank gas water heaters, high-efficiency gas and electric heaters, different type of tankless water heaters, Hybrid on-demand water heaters, products which move into the “condensing” space, and the re-emerging technologies of electric heat pump and solar water heater. Plumbers should make homeowners aware that their water heater is one of the longest-lasting appliances in the home with warranties available on some of the tankless and hybrids that far exceed other appliances. Since it is a long term investment, investing in super high-efficiency water heaters can make sense. For instance hybrids, properly installed tankless units, and solar water heating systems offer rapid paybacks. This in part due to lower operating costs, but when combined with federal tax credits and other state and local rebates, it’s an even more attractive investment. While the homeowner will pocket hundreds of dollars in energy savings this year, the savings will increase in years to come as energy cost continues to climb.

As a Licensed Green Plumber I will give you some things you need to know when choosing a water heater and help answer some misconceptions.  First off the terms ‘Tankless’ and ‘Hybrid’ is NOT the same thing.  Although they both are considered “On-Demand” water heaters, they are not the same. Also they are not ‘Instant’ water heaters (a small unit installed at each fixture in the house is the exception). A tankless water heater has limitations. This is where plumbers need to become more savvy in terms of recommending where to install a tankless water heater in a home. A hybrid water heater combines the flow capacity of traditional tanks with the continuity of modern tankless to supply consistent endless hot water with good consistent pressure. For example: The Eternal hybrid’s burner is dual activated by both a thermostat (similar to a tank) or flow sensing (similar to a tankless).  This intelligent control means Eternal has no start up lag, to waste water and is compatible to all water saving devices and Water Sense shower heads.

The “Hybrid” description is sometimes expanded beyond just one product to incorporate various components into combination systems.  Example: Combine solar panels, storage tank, radiant floor heating and one Eternal Hybrid water heater to give endless hot water and space heating to a home. Combinations like this greatly enhance annual energy savings.

The tankless water heater limitations to consider are: If not positioned properly in a home it can waste water while waiting for hot water.  If the demand for hot water is too low some units won’t turn on or they will go on and off repeatedly and produce inconsistent temperature swings when multiple fixtures are asking for hot water.  The cold water sandwich example: Person one showers and turns the water off when done, person two gets in shower turns water on gets hot water initially because there is hot water left in pipes, then gets a burst of cold water because the water heater turned off after person one and it takes a certain amount of flow to tell the unit to turn back on again and sense what temperature is asked for. If you turn the hot on and wait for the cold water sandwich to pass, then you are wasting water and energy. Tankless have no pre-heated water, therefore they take at least a half gallon of volume to flow through the sensors to turn them on which also wastes water. Tankless can burn up to 150k to 200k BTU’s, where most residential tanks never exceed 40K BTU’s.  The highest efficiency ratings for most tankless units are above the 150k BTU burning rate, were most residential usage is under 100k BTU’s and efficiency ratings are less on their lower burn cycle. Proper sizing and venting are also critical issues. Gas pipe sizing needs to be re-calculated for the whole house using the UPC code standards to accommodate all appliances BTU ratings which generally means upsizing the gas line to install a tankless. Example:  Old tank water heater averages at 40k BTU’s, where as a new tankless can go up to 200k BTU’s. If the gas pipe is insufficient for all appliances it can cause an improper burn either for the new water heater or another appliance which can burn less efficient and potentially unhealthy. Lastly changing of the gas piping may not be cost effective in the long run for some customers. Plumbers need to help with this information for each customer. The Tankless water heater positives are that if installed correctly in a remodel or in a new design build home were the plumbing pipe runs are not that long they can be efficient and definitely space saving. Again a licensed plumber should help with this information.

Hybrid is simply the best characteristics of both tank and tankless. A condensing model with higher efficiency ratings that will perform like a tankless in the long-draw scenario and like a tank in the simultaneous/multiple fixture draw scenario with a built in buffer tank you don’t need the increased BTU’s that the larger tankless units need to provide hot water on-the-fly. This is where Hybrids perform at higher efficiency ratings, on the lower burn cycles, which is where most residential applications cycle most. Some Hybrids have stainless steel construction for longer warranties (up to twenty years). Also no pressure loss with multiple fixtures running and there’s no wasting water, or cold water sandwich. Hybrids can perform two or more functions, with special connections and controls you can operate radiant heating, solar back up water heating, and easily adapt to thermal, geothermal, or other renewable energy sources. One drawback to both Tankless and Hybrid are that they both need to have electricity to run there control panel. Although minimal power is used, if there is a power outage there is no hot water unlike previous generation gas tank water heaters.

I can go on and on about pluses and minuses about each type of water heater or water heater system on the market today, but the bottom line is each home is different not just in size or how the pipes run but also what the habits are from the people who live there.  So when the time comes to consider changing out the water heater in your home or business, consider all of your options because after all this is a decision that can improve your carbon footprint (energy usage) and help sustain our community. It should not be considered a no-brainer decision. If you have any questions regarding this article or your home water heating system you can go to my website www.plumbpower.com and I will answer any questions for you.