On Demand Water Heater ?

gm280

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I presently have a 50 gallon electric water heater system. And for the most part there is nothing wrong with it. But we have been wondering about on demand water heater systems. Has anybody used an Electric On Demand water heater system? And if so how do you like it? I am not looking to save any amount of money, but more of a not running out of hot water is the interest. Any response is welcomed response. And I don't have any means to use gas heater on demand unit because we have no gas running in our neighborhood... Thanks in advance!
 

dwco5051

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Electric whole house water heaters are not really practical due to the large current draw. Even with the warmer supply water in the South a house may need major rewiring to update the electrical entrance. Even the gas heaters will not usually pay for their selves when you life cycle the initial cost against the savings.
 

gm280

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Electric whole house water heaters are not really practical due to the large current draw. Even with the warmer supply water in the South a house may need major rewiring to update the electrical entrance. Even the gas heaters will not usually pay for their selves when you life cycle the initial cost against the savings.

If you are talking about the fact that you have to install THREE different larger 40 amp breakers to the on demand heater, I know about that and I have a 400 amp service system installed at the house already. And the distance to run those 40 amp breaker wires from the breaker box to the on demand heater is a mere few feet. So that isn't a show stopper. I am more concerned with how well they heat the water once the demand is there. Do they keep up with the demand? I honestly don't know that answer...
 
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I use to live in the UK and I installed a few whole house and instant showers and they worked great.

Now im in florida and ive installed 4 at work. 2 were small units designed for a sink and 2 were large units. I found them to be a pile of junk. Now I know that electricity is electricity (UK hertz is slightly different but that doesn't affect the units) so I had to wonder why the American ones didn't work as well. After a lot of thought I realized that due to plumbing code in the UK (anti-back flow) the water pressure in a british house is a lot lower (maybe 5psi) than a home in florida. Now the units do come with restriction plugs to reduce the flow rate so they can be made to work but it seems like you are being ripped off when you turn on the tap and it runs slower than it use to.
Are you considering this as a money saver. I was kinda interested in the hot water heaters with the reverse ac unit on top. The waste energy is cold air which seems a great idea in florida but ive never seen one run so im a bit apprehensive to spend the money before I know if the unit is to loud for the area I want to install it.
 
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Chad Flaugher

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I've had clients make the switch over the years to Tank less water heaters. Bare in mind, these were gas. Wonderful idea, and they couldn't be happier. It is a costly conversion (tank to tank less), but does save money. I can't see how an electric unit would be nearly as effective. Just my 2 cents!
 

MTboatguy

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One thing you need to look at, is what is the temp of the water coming into the house, those heaters can only raise it a certain amount. I looked at them a couple of years ago for our place, but it was a no go, our water comes out of the ground at 36 degrees, there was none of the current ones that would heat the water to a decent temp quick enough, I did put a supplemental on my bath tub jacuzzi, because our hot water heater is not quite big enough to get the tub full, I put it inline on the hot water feed to the tub, which comes directly from the hot water heater, when it finally gets to the bottom of the tank and is running cooler water the instant heat takes over to finish the job of filling the tub. But you really need to have a person do an assessment on your house and your water feed to figure out if it will be a benefit or a hindrance from what you have now.
 

Cofe

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We recently had a contractor install 125 units on a hotel. He advised he would only install and warrant the gas units because the electric ones were pure junk.
 

JASinIL2006

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One thing you need to look at, is what is the temp of the water coming into the house, those heaters can only raise it a certain amount. I looked at them a couple of years ago for our place, but it was a no go, our water comes out of the ground at 36 degrees, there was none of the current ones that would heat the water to a decent temp quick enough, I did put a supplemental on my bath tub jacuzzi, because our hot water heater is not quite big enough to get the tub full, I put it inline on the hot water feed to the tub, which comes directly from the hot water heater, when it finally gets to the bottom of the tank and is running cooler water the instant heat takes over to finish the job of filling the tub. But you really need to have a person do an assessment on your house and your water feed to figure out if it will be a benefit or a hindrance from what you have now.

Our situation was similar. I found a website that would help calculate your needs for a tankless (gas) heater, based on water temp coming into the house during the coldest months and max amount of water used at any one time. I found I would need two of the units, the cost of which would dwarf any savings due to less gas used. It just wasn't economical for us.
 

dwco5051

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The local plumbing supply house I go to whenever I go to town (read free coffee and a chance to bs with my hunting buddies) will not even sell the electric models. They will special order them for contractors that are going to use them for point of use situations in large houses.

As a side note beginning in April of this year new government energy standards for water heaters take effect which is really going to give some sticker shock for anyone buying a heater made after that date. The new electric storage heaters will be physically much larger in overall dimension than the ones they replace . A few people replacing heaters in tight spaces will find the new ones may not fit. Heaters larger than 55 gallons will be much more expensive heat pump units.
 
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TexMonty

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One of my businesses is plumbing. All of the responses were valid. Let me see if I can be clear on this. In a new installation tankless by all means. I have two gas tankless and love them. They were installed during construction of the house. My partner has the usual 50 gallon tank type and when his went out what did we replace them with - the usual 50 gallon tank type.
 

Gyrene

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The responses agree with what I found doing my own research - the gas ones can work, electric often won't keep up.
I would think a solution in your case would be to insert an on-demand heater before your existing HW heater.
 

MTboatguy

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The responses agree with what I found doing my own research - the gas ones can work, electric often won't keep up.
I would think a solution in your case would be to insert an on-demand heater before your existing HW heater.

I did mine on the exit of the hot water side going to my jacuzzi tub, even as you run out of hot water it is still warm, so with the booster inline it brings it back up to temp very quickly, putting it before the heater could be defeating the purpose due to the fact you are going to have cold water hitting it, then warm, then mixing with the water in the tank, I don't know that would help the situation overall to keep the whole house at temp. Now in my situation, the only place we have any trouble is with the jacuzzi tub, the rest of the outlets in the house are low flow types and we never run out of hot water at any of the showers or the dishwasher or sinks, which is why I just put a supplemental on the hot water feed to the tub.
 
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ezbtr

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When I used to travel for work, we used to have our guys install an under the sink version in cold climates in the bathrooms for hot water, I think they were direct AC plugins???
 
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