Tankless Hot Water Heater
We install tankless hot water heaters within 20 miles of NW Atlanta and Marietta, GA.
Tankless hot water heaters are “green” and all the rage lately around Atlanta and Marietta. We’ve installed gas and electric, residential and commercial, multiple units connected in parallel and even remote thermostats.
The first tankless hot water heater we installed years ago was a Takagi light commercial size gas unit with a remote thermostat. We installed it as part of a large remodel of a very old farm house in Alpharetta, Ga.
Our client had never even thought of wanting a tankless hot water heater and had been planning on us salvaging her existing 5-7 year old 50 gallon gas hot water heater. Things changed when they went to Ferguson’s Enterprises, the largest plumbing fixture supplier in the Southeast, and picked out a whole shower system by Hans Grohe. It was serious and had quite a few body sprays.
I was looking at the shower valve and reading the instructions when I realized it was calling for a 3/4? hot water supply pipe. I thought “wow, 1/2? carries 4 gallons of hot water per minute, but 3/4? carries up to 9 gallons of hot water per minute”. Then it hit me, 50 gallons divided by 9 gallons per minute was less than 6 minutes. I had heard about the new tankless hot water heaters, but right then, I was starting to think about them quickly.
When I asked the customer how long she and her husband showered for and how hot, she said they showered at least 30 minutes back to back each morning and they liked it almost totally hot. When I shared my math with her, she wasn’t very happy with the selection lady at Ferguson’s who didn’t ever even ask her what size or type of water heater would be supplying the hot water for her high volume shower system.
It suddenly became my job to learn all I could about tankless hot water heaters and figure out which size, style and brand would be the best value in this specific situation. Tankless hot water heaters were still pretty cutting edge and were early enough in the product development cycle that fortunately for me, there were only a few brands to research.
At the time, Takagi was an early standout brand of tankless hot water heater that sort of reminded us of the Japanese import cars that were such good values at the time. Takagi also had a light commercial gas tankless hot water heater that would make enough hot water, as many residential gas units just weren’t high enough btu’s yet. They also had a remote thermostat so my clients could turn it up really hot just for the shower marathon each morning.
Our story had a happy ending, the tankless hot water heater worked wonderfully and my customers were thrilled. None the less, some cautions about these wonderful tankless hot water heaters should be mentioned.
Tankless hot water heaters are about 4-5 times as expensive as traditional gas or electric water heaters and about double the cost of electric heat pump water heaters. For even a median size house, you’ll need either a large gas tankless hot water heater or two electric tankless hot water heaters run in parallel. Fortunately, there is still a 30% tax credit, up to a maximum of $1,500 for installing a tankless hot water heater.
Never let anyone install two or more electric water heaters in series. This is the primary reason that electric tankless hot water heaters have so many complaints about not making enough hot water. A, they don’t install enough units as they are only about 50% as strong as the gas units and B, if you install them in series, it constricts and limits the added benefit of the added electric hot water heaters.
If you currently have a traditional electric water heater powered by 30 amps, you’ll either need to replace it with two 60 amp circuits to run two electric tankless hot water heaters or switch to gas, both of which are fairly expensive. Sometimes there isn’t enough power or amperage left in your electric panel to power two or more electric tankless hot water heaters, so you’ll have to add or up-grade your electric panel or pipe some gas to it.
If you currently have a traditional gas water heater fed by a 3/8? to 1/2? gas pipe, you’ll either need to run a new pipe that’s more like 3/4? to 1? to run a gas tankless hot water heater or run a couple of 60 amp electric circuits to run two electric tankless hot water heaters. Sometimes there isn’t enough power or amperage left in your electric panel to power two or more electric tankless hot water heaters, so you’ll have to add or up-grade your electric panel or pipe some gas to it.
If your house is large enough, with enough bathroom or people staying there regularly, it’s possible to need two or three gas tankless hot water heaters or 3-5 electric tankless hot water heaters to meet the hot water demand. Add to this, the need to vent the hot exhaust air to the outside, possibly for multiple units, and it’s easy to see how expensive this tankless hot water heater option can get.
We have a trick we’ve used to successfully stretch one gas or two electric tankless hot water heaters to handle a larger home. If a traditional tank water heater is already installed when we arrive, we leave it in place and let it act as a reservoir to hold water in front of the tankless hot water heaters. This allows the ground water that is 45-55 degrees to come to room temperature before being heated by the tankless hot water heaters. This allows the same tankless hot water heaters to heat a larger amount of water to a higher temperature quicker.
Normally the old traditional tank hot water heater is just left turned off, but if a large number of visitors comes to stay or the home owner is having a large party, the old traditional tank hot water heater can be turned back on and set to 80, 90 or even higher to give an even greater temporary assist to help the tankless hot water heaters carry the artificially high hot water demand. So as long as it wasn’t leaking, why throw the old hot water heater out when it can be kept and used as part of the new system?
If knowing tankless hot water heaters are expensive, you’re still interested in learning more or having us come to your home for a set of options and estimates, please call us at 770.591.4464
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