tankless water heaters.

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tonyou812

tonyou812

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North New Jersey
Has anyone ever had any experiance with electric tankless water heaters? I had a customer ask me about them. I personally never come accross one. They do not have natural gas available in their area. Im more concerned about if they function ok. Ive heard that some of the gas models dont have a very good low flow rate, meaning that if you have the hot water on just a little the flow sensor dosent always pick it up. Any info on past experiances would be appreciated.
 
I have had expierence with the gas and electric ones in the UK and based on the ones they use there, I would be hard put to install one in my house. Unless I could see a decent demonstration that they did more than spit lukewarm water on me.
 
A plumber friend told me that if you instal a small 5-10 gallon water heater on front of the tankless one youll get that instant hot water without the lag and it would pick up on the low flow problem some of these seem to have. I told him than whats the point of the tankless if you install a tank one in front of it? Ive been to Scotland and they have them everywhere. But they are installed at a point of use not away like in a garage or basement.
 
electricalperson said:
those tankless water heaters are becoming more popular around here. the kind ive installed were gas fired never electric. this site here makes them sound nice http://www.e-tankless.com/
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If I am doing the math right, a "low-flow" shower head
is 2.5 Gallons/minute. The "small" 50 amp/240V model
puts out 2.0 Gallons/minute with 65 degree input water
The "large" puts out 6.1 Gallons/minute and draws up
to 150 Amps. Sounds like a hefty amount of current
for an amount of water that may not be enough.

Have recently installed the natural-gas powered models
without any complaints. The thermostat is remote,
so they set the hot water temperature from the laundry
room. I have heard from plumbers that these things
sometimes clog because there is nowhere like the bottom
of the tank (in a "regular" water heater) for any debris
to accumulate, so filtering the incoming water is a good
idea. I haven't had enough experience to recommend
them strongly.
 
They click a lot as the controller tries to keep up with demand.
The water temp. varies in a more-or-less predicatable manner, so you have to watch out you're not standing under the shower when the water turns cold.
 
I work with an engineer that specializes in energy conservation. He is adamant that the instant water heaters do not save any money.

He argues the water that is wasted each time you use hot water, then the hot water that is in the pipe cools down and that heat is lost, and the long term repairs that are sometimes difficult and expensive.

His preference is to install an efficient tank(there are some that use less energy than instant) water heater and circulator pump to keep hot water readily available at each fixture. The loop must be insulated good.
 
tankless

tankless

I have only dealt with the electric "tankless heaters. The small residential ones and the largest was one in a small laundry in apartments. Had to set a sub-panel, it required 125 amp circuit. I guess the pocos love these things? To derail the post , have you seen those "boneless" chickens??? I did a job in some chicken houses, the things had about 65,000 "boneless" chickens in them! What a pittiful sight!!:D :grin:
 
I installed an Eemax tankless water heater in an home that had a nearly new 125-amp service. The Eemax the customer bought required three 40-amp, 240-volt circuits. It put out tons of hot water, but the lights flickered and went dim. Especially in the kitchen.

I then called customer service and the man said that the problem with the lights flickering/dimming was from poco's transformer being is too small.

I called poco, and I forget what kw the transformer is, but it was plenty big enough for the three homes connected to it. So we installed a 200-amp service upgrade to the folks, and still had the same problem. I installed a cloud fluorescent fixture in the kitchen, but had no other suggestions for them. (Except to toss the tankless).
 
iwire said:
Actually no, they hate them.

If an entire neighborhood went with these the power company would have issues at peak times.
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Same goes for the gas on demand water heaters. If a whole neighborhood installed them, gas pressure would be at a trickle when everyone is getting ready for work in the morning. This warning has been written about in trade magazines lately. The recent article "Going Tankless: Energy efficient hot-water heaters are making inroads in the US market, but when is tankless the right thing to do?", by Penelope Grenoble. This article not only explores the peak demand issue, but also the more common sense payback issue.
 
ItsHot said:
To derail the post , have you seen those "boneless" chickens??? I did a job in some chicken houses, the things had about 65,000 "boneless" chickens in them! What a pittiful sight!!:D :grin:
Click to expand...

boneless.jpg
 
I installed one of these just last week
http://www.stiebel-eltron-usa.com/tempra.html

Required 2 50A dedicated circuits (208/240) > The install was in the guest house of a 'flip' property that had a 90A subpanel. The 'flipper' was too cheap to pay a plumber to install a 'real' mini-tank water heater, so they picked up one of these and piped it in. Then they called me to do the wiring. I took one look at the specs and laughed out loud. I called the manufacturer, and the tech guy said to expect 35-40 amps draw on each circuit when filling a tub or taking a shower. The flipper insisted that i wire it up anyway. When i went to test it, the elements (there are 3 in each little tank) would not fire up due to lack of H2O flow. I guess these units have very fine filters to keep any debris in the pipes away from the elements. I asked the flipper if the 'plumber' bothered to blow out the lines prior to the install (the house sat vacant for a couple of years prior to the flip). I got a nice blank stare on that inquiry.
 
I installed one about a month ago. And I asked the plumber about how good they are. He said they are great for houses with a max of two baths. But very quiet when they are running and about ten seconds you will have hot water :grin:
 
dSilanskas said:
I installed one about a month ago. And I asked the plumber about how good they are. He said they are great for houses with a max of two baths. But very quiet when they are running and about ten seconds you will have hot water :grin:
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What brand?
 
The biggest one i did install was 24 KW unit but i heard there is a 36 KW unit on market but i feel that 24KW is the borderline due many time have to upgrade the service entrance system.

and yeah the POCO is not too thrilled with it and they are working on the regulations book about dealing with the dangbat tankless heaters [ both gas and electric verison ]

Merci,Marc
 
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