AO Smith Electric Water Heater (leaked)

[mark_wpduet]

researching tankless

You're right. It's not as simple as switching one for the other. It looks like they require a certain voltage on a double pole breaker. By double pole, I'm sure that means a breaker that has 2 breakers on one long pole in the breaker box. But on that double pole breaker, there is voltage. One says 50 and the other says 30. That would NOT work (at least for the ones I've looked at) so I'm sure that would have to be done by an electrician. But the breaker box is in the garage just beside the laundry room. Not far. I'm not sure if that even matters. I think it would be better the closer it is. But I'm not sure of the climate map showing the best model for your climate. Sometimes the water here in the winter will be so cold it's ridiculous. I have no clue what type would be good for 2 people. We never take showers at the same time. We never do laundry/dishwasher, run sinks while taking showers. I guess now is the time to start saving for one because I can't see this BOTTOM of the barrel Lowes 40 gallon tall A/O smith lasting that long.

 

[ea56]

After reading this thread I too looked up tankless electric water heaters, I wasn’t even aware that they existed, I thought they were only available for gas. I found the same info as Mark relates in reply #30.

I do think that we could switch to one of the mid to high output models with no problem. But the installation would absolutely require an electrician and the running of at least one more electric line to where the water heater is located, in a closet under the stairs. And also the addition of at least one more circuit breaker, so this would be a big and fairly expensive job.

That being said, we last replaced our water heater 9 years ago, it is one of the Low Boy 40 gal. models by Rheem, and works fine. The previous WH was over 20 years old, and when it failed it wasn’t all at once, it just stopped producing enough hot water. So, if and when this one begins to crap out I will certainly look into replacing it with a tankless electric WH, the long term savings in electricity would soon offset the extra expense. BTW, the safety release valve drains into our backyard, I’ve never heard if a safety release valve opening and flooding the interior of the dwelling. We even had a safety release valve for the WH in the home my family lived in when I was a teen, and it was built in 1961. Once, when I and my siblings were coming home from school, Mom was at work, there was water shooting out from the front of the house, from the overheated electric WH. So this safety feature has been around for over 50 years.

Eddie[this post was last edited: 9/21/2019-19:29]

 

[circlew]

Electric tankless water heaters large enough to serve an entire house of normal size usually require at least 2 or 3 240 volt circuits of 50 to 60 amps each. These breakers are usually in a separate panel of either 150 or 200 amps. This is in addition to the panel or panels serving other loads such as lighting, appliances and HVAC. Therefore, a main service of at least 400 amps is usually required.

The markings on the handles of circuit breakers indicate the rating in amps, such as 20, 50, 225, etc. In a residential occupancy, a single pole breaker is for 120 volt circuits, and double pole for single phase 240 or 208 volt circuits. On rare occasions you may find triple pole breakers for 3 phase 240 or 208 volt loads.

 

[mattl]

Tankless are OK for some folks, I'd opt out.  Looked into them a while back but I like my water HOT, tankless max out at about 120 from what I read.  I keep my tank at the highest temp, about 150+ and like it that way.  Dishes flash dry, laundry on hot is hot.

 

[mark_wpduet]

Well

I'm not 100% sure but I think I remember upping my old water heater temp to 135 from 120 or 125. Whatever it was on at the factory I bumped it up like 10 degrees. With this new one, we just left it a default....and I can tell the water isn't quite as hot....but it's PLENTY hot enough. Hot enough so my hands can't stand it on full hot, I have to mix hot/cold. Plus, the washer has a built in heater as does dishwasher....so I feel like as long as it's hot enough the way it is I'm just going to leave it........BUT, as I type this I think I just remembered WHY I turned it up a long time ago. It was because of a post on this forum about bacteria growing it water tanks that are not set at a hot enough temp.

 

[DADoES]

 
Residential-oriented tankless typically allows maximum setpoint of 140°F.  Commercial-oriented units may go higher.

A separate subpanel is required here for all electric water heaters, not sure when that went into effect.  The last tank replacement at work had a subpanel added.

My electric tankless is on a 120 amp circuit.
Two 60-amp breakers in the main subpanel, 1-3 and 5-7 (9-11 is the range).
The dedicated subpanel inches away divides the two 60-amp circuits into four circuits feeding into the unit, each with two 40-amp breakers.  It has four 7,200-watt elements.

 

[petek]

I went through the same thing about 6 months ago. Got up one morning and had no hot water.. went down to the basement to check and found a few inches of water just about to cross the threshold of the furnace/work room into the carpeted rek room.. water gushing out the gas water heater.. Same deal, no floor drain and there's a boiler in there as well. I can't figure that one out. I've never lived in a house without a basement floor drain . Got that all sopped up with the wet/dry vac. Because of regulations now in force here in Ontario they couldn't install a new gas heater because the old one shared the flue with the boiler. And because the gas meter was outside right about where a new flue would go through the wall it was too close (more regulations) to the meters regulator.. has to be at least 6 ft away. So I installed a Rheem electric.

I was pissed off at myself because I had bought a cheap battery water alarm but had never taken it out of its package.. I have now.. and I bought about 6 more off Amazon and have them placed in all bathrooms and under sinks.

Lo and behold I get up this morning and hear the dreaded sound of the one in the basement going off a few feet from the water heater.. but for some reason it's not wet down there... so not sure why it went off.. I honestly felt sick to my stomach when I heard it. I really don't want to go through that nightmare.

btw mine was set at 140 out of the box.. I dropped it to 122 and that seems to work fine for the dishwasher. Laundry is pretty much always done with warm or cold washes.

 

[iowabear]

Electric WH

In this area an electric WH would never make sense due to the price of electricity.

 

A tankless one would represent an even greater risk should our utility ever implement mandatory residential demand charges. They already have an optional experimental tariff for it.

 

[mark_wpduet]

Codes

Yes! There are codes for EVERYTHING but not a floor drain where a water heater tank holding gallons of water that are known to leak at end of life or even for other reasons is located.

This cheap water heater we bought......the drain valve is PLASTIC. How's that for quality? But I can understand because of its price point.

On a YouTube video I read a comment and I busted out laughing. Someone said: It's not a "hot water heater", it's a "water heater" If the water was already hot, it wouldn't need heating!

Anyway.....Here's the one we bought

https://www.lowes.com/pd/A-O-Smith-...uble-Element-Electric-Water-Heater/1000213649

 

[ea56]

Codes

When we had our WH replaced in 2010 it was mandatory that we had a drain and drain pan installed under the WH, and also even though its electric and a low boy, less likely to tip over in a quake, we also had to have it strapped to the wall, according to code in our local. This increased the installation charge considerably, but was good insurance against future damage from any leakage.

Eddie

 

[mark_wpduet]

One thing I forgot to mention

when we bought this at Lowes, we had to pay a $70 fee to the city and fill out a form because we were installing it ourselves. Supposedly, whether it's installed professionally or on your own, someone is supposed to come out and check to make sure it was installed correctly.....but they NEVER or RARELY do. They just want the money.

 

[DADoES]

 
Shower this evening.  Flow-rate that I typically run (less than full-open), setpoint 103°F, tankless reported:  input temp 80°F, 1.4 GPM, 16% capacity.

 

[mark_wpduet]

the more I learn

the more I'm not sure electric tankless would be a good idea for areas too far north where the water gets COLD in the wintertime. Like, say you've had weeks where it's been super cold and the water temp is like 38 to 40 F or something like that.... I wonder how an electric tankless would handle that? I'm sure it can get cold in Texas as well.

 

[combo52]

Tankless Water Heaters Etc.

The chief advantage of tankless WHs is space saving and the ability of unlimited supply of hot water, There are also many disadvantages as well.

 

TWHs can not supply a steady supply of water over 120F when several faucets are being used at the same time in a house when incoming water temperature is very cold [ under 45F ]

 

ETWHs are especially bad at this, in addition ETWHs put very high demands on electrical supply systems are are prone to all kinds of wiring and circuit breaker failures, there are no other appliances in modern homes that use anywhere near the amount of power these WHs consume, even electric furnaces are not that bad and there are darn few electric furnaces in use now that heat pumps are so popular even up North.

 

TWHs often actually raise energy usage when people find out their time in the shower has no limit, this is again true in homes where there are a number of people living there and with a tank type WH you had to look out for one another.

 

Heat loss from electric and Heat-Pump WHs is very small because of very good insulation and the lack of a flue running up the center of the tank that is always loosing heat up the flue.

 

John L.

 

 

[turbokinetic]

Response to John L reply #43...

 

I had often wondered how much power tankless water heaters use. I have no need for one, as my home doesn't have space constraints and the current water heater is in its own room, and is double-insulated.

 

My curiosity was piqued when installing an all electric pressure washer.  This has a 27.5KW heating system on it. With the 7.5HP motor running and the heat on, the demand is just about 33KW and almost 130 amps at 240V. This is a large percentage of the building's 200A service capacity.  I don't see how a tankless electric water heater could be practical for a home with a smaller electrical service capacity; unless you only expected "warm" not "piping hot" water and only one hot water tap was on at a time.

 

The power company, building engineering, etc. would all be happiest with water heaters that use the minimum power, and run constantly. In other words, a huge tank with small elements. That would be best on the power system. These very high power loads which switch on and off are stressful on the system; where the same energy consumption spread over a 24 hour period is much better.

 

 

 

[ea56]

After reading more about the power requirements for an ETWH it's clear to me that this isn’t a viable alternative for our home.

We’ll stick with the tried and true conventional EWH. Due to space limitations we have to go with the Low Boy models, and thats OK too. Having lived in an all electric home for 25 years we are very good at using our electricity in a conservative manner, and are able to keep our power costs from getting too high.

Eddie

 

[Chetlaham]

A tank-less water heater typically requires that the home have a 150-200amp service (at least) and its a REALLY good idea you contact the power company about it as they typically size their equipment to the actual anticipated load (not conservative NEC load calcs) which do not take an extra 25kw-40kw of load into account. Meaning you could actually burn up their service drop or pole transformer in the middle of winter.

 

[mark_wpduet]

I've learned so much

the past couple of weeks about water heaters that I really NEVER KNEW. The sacrificial anode rod that's in most water heaters and needs to be changed over time! Even watching youtube videos of people changing them.....It looks tricky depending on the water heater and sometimes it looks EASY. Also, the type of metal in the anode rod can be totally different from area to area, depending on water. No wonder there's sediment in water heaters because that rod disintegrates. So not only do you need to flush the water heater, the anode rod needs to be changed too. Every place I've ever lived has been all electric, and I've never known anyone to do any of this with their hot water heaters.

 

[mattl]

Gas is the best option for me.  I have a 40 gallon higher efficiency tank, set as hot as it will go, and my summer gas bill is ~$20 - including a gas cooktop and dryer.  I think it would be hard to beat with any other type.

 

[circlew]

From 1974 until about 10 years ago, my house had a Weil-McLain electric boiler for the baseboard hot water heat. It drew about 120 amps if all four elements were energized, which happened in very cold weather. It was connected to its own 150 A main breaker, which had its own line (2/0 AL) coming from the meter. At the time of the boilers installation, the overhead service drop was replaced with heavy duty wiring with an ampacity of 400. In the 30+ years it was in service, never once did we have any issues with the breaker tripping. However, the first winter we had it, on a very cold day, we woke up in a cold house with no electric. The two houses across the street were also out. The power company replaced a fuse on the transformer, but it blew out again that evening. The next day they came back, and installed a new transformer just for our house. After that, no trouble associated with the electrical service. The boiler elements came on in stages, according to how much heat was required, so no huge load all at once. The voltage on the other circuits (in another panel) stayed stable, with very little drop even when boiler operating on all elements.

A premium quality panelboard, such as Eaton CH series or Square D QO series, have plated copper bus bars instead of aluminum as found on cheaper models. These panels and their breakers should not have any problems withstanding heavier load such as these tankless heaters, as long as panel is of the proper amp rating, and the associated wiring is properly installed.

 

[askolover]

Well I had planned to go tankless a few years ago until I found this page.

http://www.waterheaterrescue.com/Longevity/tankless-water-heaters.html
I'll stick with a tank.

 

[mark_wpduet]

Same

I think the best option would be heat pump water heaters. But they are EXPENSIVE, but supposedly pay for themselves and then some over time. I was reading some reviews on them. One person said, heats water, low energy, self-cleaning, what more do you want? I thought, self-cleaning? How?

My cheap heater I just bought is doing really well. I hardly ever hear it heating water UNLESS one of us has showered. I take long showers and I haven't ran out at all. Something I just noticed in the description of mine is that it has "copper" heating elements vs stainless steel (LOL). I'm not surprised.

I may get brave and drain mine after six months like the manual says to do, or at least connect the hose and just let water run through it.

 

[DADoES]

 
I've not had any issues getting sufficient heated water out of it or any electrical supply failures for the duration of 15+ years with the tankless.

There is no natural gas service in the little neighborhood outside town where my house is located.  Propane would be the alternative.  Both bathrooms have whirlpool tubs (not Jacuzzi brand) and a standard 40 or 50 gal tank heater couldn't handle filling them so perhaps the builder went with tankless on that point instead of two tank water heaters or one super-sized ... my understanding is that he also had the tankless unit already on-hand, having placed them in one or two other builds.

Tankless, either gas or electric, surely is not for every situation, and retrofitting either type to an existing tank installation often involves "problems."

 

[mark_wpduet]

Just watched a video

If I spent $1500 dollars on a heat pump hybrid electric water heater (not counting potential discounts from Lowes or Home Depot and the possible rebate from the power company), by year 5, total spent on hybrid water heater would be around $2200 (that's including energy to use it over those 5 years, but possibly less than that with rebates or discounts)

This $389 water heater that I have. By year 5, this heater will have cost $2650.

But you still have to drain/flush, change anode in ALL OF THEM (from what I understand). Plus, you never know if there may be other costs such as hiring a plumber, etc., will add to those costs.

I do wonder though....It sounds like a great thing in the summer, but when it's operating in the winter it will be "cooling" the air around it, not heating it. Not sure how that factors in if it's really cold outside.

I'm definitely going to start saving for one.

Also interesting that the Hybrid electric heater plugs into a regular outlet (LOL)

 

[askolover]

I remember back in the 80's the TVA (who produces our electricity) had a HP water heater on display at one of the energy shows at Regency Square Mall in Florence, AL.  My dad picked up some brochures on them but ultimately we just switched over to gas since the city was giving away AO Smith gas water heaters for FREE to switch.  That water heater lasted almost 30 years!