Stevens Plumbing Heating & Air Conditioning
Energy saving tankless water heaters are being promoted by many plumbing contractors as a step towards “going green”.
Well, this may be an unpopular opinion in this day and age, when “going green” with all things, including all things plumbing, is so popular, but here goes: a tankless water heater may not be best for you!
Why? Because of the cost of a tankless water heater system.
Yes, a tankless water heater is much more efficient than traditional, tank type water heaters. But are the energy savings enough to justify the cost?
In the case of an existing home, converting your home’s plumbing and gas or electrical system to accommodate a tankless water heater might make you think twice.
Most tankless water heaters are gas.
In order to retrofit a tankless water heater into your existing home, we have to begin by enlarging the gas line from 1/2 inch to 3/4 of an inch – all the way from the water heater to the meter, which can be a considerable distance, and a considerable cost. In addition, we also have to change the venting from the heater through the roof – another costly process.
What if your tankless water heater is electric?
Even if your home is all electric, the cost of converting from a traditional water heater to a tankless can be high. A traditional, tank type heater uses 220v with a 30 amp breaker, while a tankless water heater requires 120 amps, meaning an electrician will have to increase the size of your electrical service (typically by adding an electrical subpanel) in order to provide the needed power for a tankless water heater.
So, gas or electric, converting your home from a traditional tank type water heater to a tankless water heater is costly. Add in the additional cost of the tankless heater itself, and you can see you’ll be making quite an investment in this conversion.
What about a new home? A tankless water heater still might not be the best solution.
The cost of a tankless water heater even during initial construction of a home is higher than the cost of installing a traditional water heater (about 3x the cost of a tank type heater). And depending on the size of the home and lifestyle factors (how many hot water consuming devices might be in use at one time – for instance, do you need to run the dishwasher and do laundry at the same time? Or, are showers and baths simultaneous?) many homes will need at least two tankless water heater systems to provide adequate hot water throughout the house. If you do decide to have two tankless water heaters installed, how much will the additional gas or electrical requirements increase your home construction costs?
But, you say, the energy cost savings over the life of a tankless water heater will make up for the additional up front costs.
Maybe not! Here’s an excerpt from a paper by Dr.William R. Hoover of the A.O.Smith Corporate Technology Center:
“…. based on calculations comparing the least efficient gas storage water heater with the most efficient tankless water heater, the maximum estimated annual cost savings is just $59.”(1)
Just $59 a year in energy savings!! How long will it take you to recover your investment and begin to actually see a savings? Yes, tankless water heaters are said to last much longer than tank type but even the best estimates are a lifespan of twenty years. And, keep in mind that since tankless water heaters haven’t been in common use for very long, no one can say for sure what the actual lifespan may be.
There are times when tankless water heaters are a good option. They’re compact, so if space is an issue tankless might be the right solution. But for most homeowners, a traditional tank type water heater is still best.
Clearly, the potential energy cost savings just doesn’t offset the large investment required to install a tankless water heater system. Not surprisingly, most of the time when we’re called out to replace a water heater for someone who’s considering having a tankless installed, the higher cost is enough of a disincentive to change their minds.
Here’s how Dr. Hoover sums it up:
“Tankless water heaters have advantages. They are compact and are easy to drain; consequently, they could be ideal for applications where space is a premium or in small vacation homes. In addition, they could serve quite effectively in point of use applications. However, their use as the central source of hot water in a residence should be carefully considered. While tankless water heaters offer some modest energy cost savings over storage water heaters, those minimal gains are at the expense of higher initial costs, higher installation
costs, higher maintenance costs and the potential need for lifestyle changes to accommodate the limited flow rate output of tankless water heaters. In addition, with the coming increase in Energy Factor required by NECA II, the Energy Factor differences between tankless and storage water heaters will become even smaller.”(1)
Of course, if environmental issues are of primary concern to you then “going green” may be worth the cost. Only you can decide what’s best for you, your family, and your budget. Our experienced plumbers can install whatever type of water heater you need or want.
Questions? Give us a call! An experience plumber is always available during business hours to answer your questions, with no cost or obligation to you.
Stevens Plumbing Heating & Air Conditioning