Hot water heater elements keep burning out.

Is the water supply not restricted or with insufficient pressure to replace the outflow fast enough?

It has adequate water flow and pressure. The tank is full and air is bled off before turning the power on.

Additionally is the oil level able to keep the heating element well covered ?

Are you changing the thermostats every time ? if not are the thermostats malfunctioning/ not properly picking the temperature ?

Are you sure that the elements are not rated for 110V ? (though you have already said it is 240/208V still check)

Not sure but I don't think the tank uses oil? I haven't changed the thermostats out every time only once. I changed them out about 3 or 4 elements ago. The elements are rated for the 240/208V. I have used both the 4500w and the 3300w and both seemed to last about the same time.

Sorry meant water (working in industry with so many types of furnaces and heaters has their own disadvantages, and you always have wardrobe malfunctions - things slip out what should not )

What size are your supply lines?On a 50 gal water heater you should have no less than a 3/4" supply line. If the upper element is burning out first then your tank is not refilling fast enough and your element is "overheating". If it's getting to the point where the lower element is going also then you may have a blockage in your supply.

When does this occur most often? Early in the day, just after all the showers? Soon after the 2nd or 3rd load of laundry (in a row)?

You may want to remove the supply and return lines and check for blockages both in the lines and in the tank connections. If the supply is 1/2", then you need to change it to 3/4". The only other obvious thing, as mentioned by Hendrik, would be poor pressure.

Good luck.

The are 3/4". I haven't noticed a pattern with which element is going out first. I change the top first but sometimes it is ok (but I change it out anyway) and then I change the bottom and it was bad. I am on city water and have never noticed having low flow or pressure. I will check the lines for restrictions. I have turned up the temp from the "A" setting to the "B" setting to help the dishwasher clean better. Could that be causing the element to over heat or work harder? I know heaters that are 10 years old and haven't had to replace anything.

I forgot to answer the question about when the elements burn out. We notice the hot water problem in the evenings usually after dishes. Someone will go take a shower and they run out of hot water. When the heater is working properly we don't ever run out of hot water even there is 3 showers in a row. Thank you all for your replies.

You need to check the voltage with a voltmeter, both under no load and then fully loaded...Then check the amp draw....The watt rating should equal the voltage reading times the amp draw...You could have a loose connection or damaged connection at the circuit breaker....The water heater could have been upgraded to a larger capacity than the original, requiring a larger wire size and breaker....this setup should be on a 50 amp circuit with #8 wire size...In any case the problem most likely is going to be associated with the voltage supply in some way...

Thanks for the reply. This is a new house (2005) and it is the original water heater. I checked the breaker and it is 50 amp. Not sure about the wire size, I need to take the cover off the panel to see. I will check the wire connections and when my friend gets here with his multi meter I will do the other checks. Thanks for the great advise.

My experience here with those kind of problems is NOT the amperage or the voltage.

There's a town in southern Minnesota that absolutely cannot keep water heaters working for more than a few years. (electric or gas)

It all "boils" down (scuze the pun) to the chemicals in the water. Water softeners seem to have no effect either.

Try having your water analyzed and see if anything is found.

I tend to go with your comment 100% because as he put it in his posting 'the elements are clean except for the burnt out ones'.

This is already means that the clean ones probably never get switched on while the damaged ones take on all the loads and naturally, if the water is hard then he will have scale build ups which result in premature failures of some of the elements.

Waters in many places are just hard and I do not know what the self cleaning is about but, if that includes a softener to put in then he probably doesn't or that part is faulty.

When you say the "elements are burned out" what does this mean?

Look at the surface of the element. is it scaled? Is is "orange peeled" This means the element has overheated and the inner coil has opened and contacted the SST sheath. This acts as a welder.

Change the element to a Inconel sheath, has a higher working temperature, 1100 F.

good luck,

Art

When I say the elements are burned out I mean that they usually are burned clean through or a piece of the element is missing. One time the element burned out on the flange part and it was leaking water. The elements have a slight coating of the white calcium looking stuff but I think that is pretty normal. I will look for Inconel elements and give them a try. I will also do the electrical checks. I have been buying the replacement elements at Home Depot. Maybe they are selling junk? Thanks for the reply.

The home depot units have a high possibility of being totally "Chinese junk" or commonly called, a sailing ship......!

Buy quality, your time is also worthwhile and valuable.....

Do you live in Rochester, NY, by any chance? That gave me all sorts of issues. Even East of Rochester you might have the same issue, but Buffalo and West or SouthWest you're fine. But Hemlock Lake is small and unchanging, rich in minerals from when the glaciers last waved goodbye.

Unfortunately, I do not know what you can do about it. If you don't see mineral buildup, it probably isn't the hardness, right? You can filter drinking water but how do you stay ahead of a 50 gallon hot water heater?

Here is one idea. I AM ONLY GUESSING. But if you think your issue is at least compounded by high temperatures, you might try running two hot water heaters in parallel (perhaps the first one could be a simpler affair, just getting the water warm enough to never tax your final system and maybe even giving you a built-in pressure boost). They do say such a setup can pay for itself over many years, due to both lower energy use and lower maintenance/replacment costs.

Just a thought - remember that I am only speculating that reduced loading could help, and only because of that other town that had gremlins in their hot water heaters. Again, if you're in Rochester, ask someone to hit the Xerox "Services Forum" for you. It has been running just like this one since the late '70's, but it's local. Someone on that forum will know the scoop, I suspect.

Good Luck.

I live in the Tri-Cities, Washington state. The funny thing is my neighbors and friends don't have these issues. The water here is pretty hard though.

Hi Cartman,

I used to live in Kennewick - worked at Battelle. Had to leave there for the humid East coast and am now in freezing Ohio.

I haven't read all the posts here, but I'm placing my money on the dip-tube issue.

Hope you get the problem solved.

Mike

I agree with guest's reply. It's almost certainly the water. The nichrome elements in really old electric water heaters could overheat even while fully immersed, but the jacket temperature of the calrod elements in newer water heaters never exceeds the boiling temperature of water.

The elevated temperatures in a water heater accelerate corrosion. Water heaters are equipped with a sacrificial anode to forestall corrosion. Have you replaced yours?

If it isn't corrosion, it may be excessive aeration, or mechanical stresses from the installation process may be causing premature failure. It's also possible that the new elements are defective or poorly designed. You might find this company's catalog to be informative. They have been selling appliance repair parts for decades.

http://www.johnstonesupply.com/corp/Default.aspx

Have any of your neighbors experienced a similar problem? They might have discovered a less costly and inconvenient way of dealing with it than the frequent replacement of heating elements. Good luck!

I will check into the anode. Thanks for the info.

Like some of the others, my first thought was chemicals in the water, especially lime.

You mention that elements and tank are clean when the elements burn out.

This would make water chemicals less likely.

Are the thermostats of the type which press against the heater shell or are they immersed in the water?

If pressed against the shell, corrosion underneath could make them cut out at a higher temp than you would expect and cut in at a much lower temp.

The difference shouldn't drastically affect element life, just your power bill.

When working, do you get periods of very hot water? This could indicate an insulating build up under the thermostat.

Chemical corrosion still seems the most likely.

A good start would be a water analysis, which the water supply authority should be able to provide.

Next look for potential galvanic corrosion locations which may affect your elements.

Once you have a clearer idea of what you are facing, you should be able to work out a solution.

Please keep us posted.

Regards

Are the heating elements coats with a white hard coating ?

If so then you need to clean out the water heater you have hard water and the lime in the water is causing your problem.

In case you have never seen the damage hard water can do to water heater ask a plumber or look it up on the net.

Simply turn the temperature down at least 10°C for the heater and see if that helps the lifespan of the elements.....

They could simply be overheating, in spite of the water around them.

See if there is another supplier for the same element type.

Ask at the manufacturer for any tips with regard to this problem.

Get the thermostat checked out for problems...

Have a great day.

I will try that. I had turned it up one notch to help the dishwasher clean better. Maybe that is the problem. Thanks for the reply.

It's an unusual dishwasher if that would help.

If the dishwasher has an internal heater, you nearly always get cleaner dishes if you start with cold water - and as your water is electrically heated in the first place, there is no financial saving in feeding hot water to the dishwasher in the first place.

In his case, your comment:-

"and as your water is electrically heated in the first place, there is no financial saving in feeding hot water to the dishwasher in the first place."

...was correct, but I (as many others do) heat water with cheap Gas, so it is worthwhile using hot water in such cases.

Some old style machines get a short cycle with hot water, but still clean well in my experience, but modern ones do not seem to change the cycle time when using hot instead of cold.....but still I find that I can take a shorter program and still get everything sparkling, including saucepans, even on a short 40 minute "Glass" program....

My advice is to try it out, especially if you have cheap (not electrical) heated water.....you will dramatically reduce the amount of electricity the washing machine uses in heating water......eg. save money.

I will try that. Thanks Andy. It will be the simpliest thing to try and now I suspect it to be the culprit since I originally turned the temp up a notch. So obvious that I missed it. GA to go along with your collection.

Hi Cartman, Along with all the other good advice such as checking for:

proper supply voltage

actual current

sacrificial rod

you may want to check for the dip tube location. It should be in the cold water supply connection inside the tank. They also can break off in the tank.

Also verify though you schematic on the tank's control cover That the upper thermostat is controlling the upper element and lower t/stat is controlling the lower element

Good Luck

I have just read the whole thread and I fully agree with the likelihood of the dip tube not delivering the cold water to the bottom if the tank. It could be disintegrated, broken or it simply has fallen off.

It is a simple matter to check this possibility and I would try that one for sure.

That was the problem with my water heater I ones faced.

Sorry if this has been mentioned already - lots to catch up on.

If you installed this yourself and you aren't an expert, there is a good chance that when you soldered on the unit you melted off the dip tube. Just a bit too much heat and this can happen quite easily. A chatty plumber once bent my ear on that longer than any of you would imagine -- it was a huge pet peeve of his (the design issue, I mean, not the DIY'ers). If he were on this forum we would know it; he was adamant that half the world's hot water heaters had detached dip tubes.

Rochester water isn't just hard or lime, and it isn't all bad. It has those issues but many other less explainable phenomena that might not have observable symptoms. Conductivity perhaps? I must emphasize that I am just speculating here, trying to offer insights that might inspire those more knowlegable. yet this water issue also was one of my plummer's favorite subjects.

I suppose I'm just an ignorant Brit, but I was unaware that there was a Rochester in the Tri Cities region of Washington

...and in new England, many, many "Eppings" believe it or not!!!

I know of a Rochester in the west of Washington state - but the Tri Cities area is SE Washington. Is there a second Rochester in Washington - if so, where?

What sort of material were the original elements made of?

I can't seem to find a source here on the web, but you need to use elements that are made from inconel & can be run dry. I've bought them at homedepot when I was making biodiesel, they could be run totaly dry unlike the copper or ss versions.

You need a burper to purge the air, when you heat water air is released...

Talk to the neighbours - if they don't have the same problem that means it's your set-up.
Here are some semi-random notes:

Your comment "I try to make sure that the water level is full in the tank before I turn the power on" sounds like a possible clue. I hope that you are talking about a header tank, and not the hot water cylinder that you are heating - because the cylinder should never be other than full. But, in any case, if the header tank becoming empty could cause a problem, the critical timing is when you run the water from an already hot tank. Of course the header tank should never get empty - indeed, if the pressure in the tank is marginal the problem could be sucking air back down the vent pipe. If the header tank is emptying, the solution would be either a larger header tank or an extension tank with a connecting pipe would do if that is more convenient. If air is being sucked from the vent pipe, you need a larger pipe between the header tank and the cylinder. In either case, a temporary measure might be to restrict the hot water flow to the laundry and to the dishwasher using their isolation valves.

It is usual to set the thermostat for the upper heater about 5^OC (9^OF) lower than than the setting for the lower one. That will allow the upper heater to help get the water up to temperature without the risk of temperature variations in the water (due to the heating of the lower immersion heater) causing parts of the upper element to overheat.

If you run the hot water without mixing any cold, can you hold hand in it the stream for 5-seconds without without being burned? If not, you can afford to reduce the temperature of the thermostats. Alternatively, hold a thermometer under the stream - it should be between 54^OC (130^OF) and 60^OC (140^OF)

Does your tank ever make a noise when the heaters are active? That would suggest there's a problem with their location or orientation in the tank. Similarly, any bubbling or thumping noise from the tank or overflow when you run water would indicate a plumbing problem as discussed above (but you can have a problem without this sort of indication).

Is the failure at the position on the element that is highest when it is in situ? That too would suggest that it may not be continually immersed.

Finally, if the failure cause is lack of immersion, I think you are wasting money and effort changing the lower heater on the occasions that only the upper heater has failed.

Sounds like your'e only getting 110 volts to the water heater, instead of the 220 needed. Check for a loose wire, and make sure both legs of the house circuit breaker are connected properly. Low voltage will increase amperage to the point of burning out the elements.

RJAGIELSKI1

WRONG.

Heating elements are basically 99.99% resistive, so a doubling of the voltage will simultaneously double the current (amps). With heating, there will be a slight change in resistance (increase) but it is unlikely that the metal used will cause a dramatic change of resistance through heating up to the boiling point of water. So let us say, "Don't count on it!!"

Simple Ohm's law, nothing more, nothing less.....will suffice for the comparison.

I = V/R Where I = amps. V= Voltage and R = Resistance.

Assuming for example that the Heater has a resistance of 11 Ohms and is connected to 110 Volts. This give I = 110/11 = 10 Amps.

If we now connect to 220 Volts, this gives I = 220/11 = 20 amps......

Sad to say but with your electrical knowledge level YOU ARE DANGEROUS TO OTHERS AND PROBABLY YOURSELF AS WELL, keep well away from all forms of electricity!!!

Safety first at all times, even on CR4 please..........

GA from me.

I would also expect smaller bills for the gas used as well......

I would switch to gas if I could but we have no gas service here. I would have to get a tank and have it plumbed. Wouldn't be cost effective for me and I would have to deal with having the tank filled and risk running out. Good suggestion though.

Thanks for the links. I am pouring through them now. For now I replaced the elements with the ones available at the hardware store. Turned out to be the bottom element this time but I changed both. I turned down the temp. to "A" instead of "B" like I had it. Thanks Andy for the tip. I am checking the wiring with the help of a buddy. So far no issues. The plumbing was screwed type not soldered except further down the line it was copper. The house builder/plumber installed the water heater and plumbing so I don't think that is an issue. I am going to get a plumber buddy of mine to look it over to make sure. I will pull the inlet to make sure the tube is there. I am going to get the Inconel elements and replace them when one of these fail again. I am also going to install a check valve. Hopefully they wont fail. I am hoping by turning the temp down I have rid myself of the problem. Thank you all for your replys and great advise. CR4 members are truly a great bunch! I will repost if I have any more issues. I have lots to check yet and lots of info that you have provided to go through. Thanks again all.

A further thought, I believe you mentioned that the heater had a header tank. If yes, add a float switch to cut off electricity (or sound an alarm!), just before the header runs dry!!!

If, as is more likely, the flow is choked and the system is sucking air in from the vent line, that would merely provide false reassurance.

Hello Cartman069:,

Just a thought but, with the elements you have already bought and, the other stuff you plan to get, would it not be Worth getting a new heater, it would pay for itself in no time. I would get a better quality make! And before you fit it check the electric cable to see the power is as it should be.

You may have said but I can't read it from here, how long have you had the heater? And, is it a heater or boiler feeding hot water and rads?

Please you sort of found this site a help. And thanks for the feedback!

Take care..............

Cartman069 Two questions: 1. is the copper plumbing properly isolated via a dieltric fitting from the non copper plumbing? 2.Ph meter anyone? (litmus paper) You may have a highly or partially... (may vary with season or different well/suuply souce..... depends on who else is on the system.)... conduct water feeding current from the element to a grounding source. MR. GUY

Check the Anode Rod.

Anode rods corrode predictably, usually starting at the top or bottom of the rod. If the steel wire is exposed more than six inches from the top or bottom, the rod should be replaced. If the steel core wire in the middle of the rod is exposed, it should be replaced. Also, if the present diameter of the entire rod is less than half the original ¾ inch diameter (this is approximately ⅜ inch), it should be replaced.

Sometimes the calcium carbonate build-up on the rod can become hard. When this happens, it prevents the anode rod from doing its job and the lining of the tank will begin to corrode. This calcium carbonate build-up is called passivation. Unfortunately, if the anode rod is passivated, you will not be able to tell just by looking at it. Bend the rod by hand and check for flaking at the bend. If flaking does occur, replace the rod. Also, if the rod has split along its length or it is heavily pitted, you should replace it.

I have the same problem with elements burning out. One rental house has a well drilled 900 ft deep into limestone.

Instead of a water softener I just tear down the water heater about every 3 years and sit the tank, a steel tank, over a fire pit and the calicum in the bottom turns to a dust. with a long steel rod I bang loose all the junk and then begin emptying it .

We put it back togeather and it will lost about 3 to 4 years vefore the heater elements blow again. But this is still much cheaper than a water softener system with all that monthly cost and replacement junk.

Plus we can add a lot of insulation inside making more efficient.

"Hot water heater elements keep burning out."

Just curious, but if the water's already hot, why does it need a heater?

Oh, thank you sooooo much for saying that! I have been biting my tongue since I first read the thread. It got so bad that I had to get someone else to bite it for a while. ( yes, a vegetarian)

My guess is high voltage. Since the elements are purely resistive the "Voltage Rating" is simply a statement the element should run at a certain temp at a certain voltage. Even marginally high voltage, 245 volts, will make the element run hot, possible boiling the water away from the element, causing it to over heat. I would measure the voltage and if near or above the upper end of the rating add a bucking transformer to get the voltage down. Also measure the water temperature as the thermostat cycles to be sure it is cycling at the right temp. Most residential water heaters use a contact thermostat actually sensing the tank wall temperature. Poor mounting contact or any mineral build up inside the tank in the thermostat location will prevent the thermostat from seeing the water temperature and not transfer to the lower element soon enough, causing the upper element to over heat. Keep in mind "Watt Density". If the replacements are physically smaller but are the same wattage, the "watt density" will be higher, that coupled with high voltage or thermostat runaway may be putting you over the top limit for the element. Obviously just changing parts will not fix the problem. Getting actual voltages, temps and dimensions will identify the problem, then corrective measures can be taken. -- JHF

Too many variables to pin point the preceise problem. Most answers to your problem about loosing heater elements are valid, it will be very difficult to diagnose correctly. The biggest cause for failure of an electric heating element to fail is, of course, overheating - no matter what the medium being heated. In the case of water; the water is not in constant contact with the element. 1. from aeration (too hot of element for the amount water exposure), 2. Get a plumber to check for proper connections (by the way the connections at the top of your heater my be theaded pipe, but to connect to the copper house plumbing someone had to use an adaptor. If this was threaded first then soldered, the orfices to the tank my have been compromised dimishing flow. 3. Electrical; have a knowlageable person check 1. the actual voltage at the water heater elements while under load & the with a "clamp amp" check current load. In the last sceinario I have experienced voltage as high as 260 volts ( this can be corrected by a call to your power provider)

Your symptoms sound like the anode has failed. Usually the anode needs inspection each 5 years but some types of water eat it out faster then start on the elements and the tank itself. The anode is usually inserted from the top and centre of the tank. I will be due to check mine this year but will ensure I have a spare on hand first. Not checking it could prove expensive as I'm using a heat pump system and I don't want the condensor (heater part in this case) tubes corroding.

If the anode has failed, the heater elements, being SS or inconel sheathed shouldn't corrode fast enough to be a problem.

The shell of the water heater will go fairlly quickly though.

It has to be overheating - the real question is why?

Lime deposits can lead to the element getting far hotter than it should. Although lime is an excellent insulator, deposits thick enough to cause an element failure would be obvious.

If, in addition, the upper element is heating while part of the time it is out of the water, it will fail quickly, unless you use one of the high temperature elements like inconel sheathed.

Incidently, on the question of voltage; if the voltage is high, the heater will deliver more power , basically rising with the square of the voltage. If the thermostat is working properly, the element will stop heating earlier than it otherwise would. In any case, the temp of the element will be limited to about 100C because it is in contact with the water.

If voltage rises too high, the circuit breaker will trip because of the excess current drawn.

The result is that high voltage alone is unlikely to burn out your element.

The only mechanisms available seem to be corrosion, leading to sheath failure, insulation failure and burnout; or running out of water sufficiently often to allow the element to burn out.

Inconel sheathed elements are likely to fix both problems.

If you are burning both elements out, corrosion would seem the most likely, but if the water itself is that corrosive, the supply authority would be having big problems with their main distribution pipes. (These are usually cement lined steel, whereas smaller pipes are often PVC).

The culprit is then likely to be some way in which galvanic corrosion can cut out the elements.

I once heard of a boat which chopped out it's copper exhaust at a great rate. Turned out that instead of brazing a joint, the installer had used silver solder, making the copper anodic and subject to rapid corrosion.

A plumber would think he was doing a better job if he substituted silver solder for ordinary brazing, and in most cases it would be fine.

Perhaps you can look at your installation with a view to how this type of situation could have arisen.

If this is the case, none of the solutions suggested so far will stop the problem, short of using platinum sheathed elements!

Good Luck!

Improper bonding of the element and tank, element sheath setting up an anodic half cell voltage? Manganese in the water?

Like your copper pipe story, copper earth mat strips (in large installations) can be a problem causing other metals to become anodic via the equipotential bonds under some soil condition circumstances.

Overheating is pretty obvious especially when calcuim deposits are involved. The element bursts and there is calcium remains everywhere.

One more thing, is a water softener involved?

Someone has already suggested the thermostats, it could be the prob.
At the instant of switch on the element is cold and probably lower than it's working resitance, you will get a big current surge and rapid heating with associated stresses on the element.
If the 'stat contacts are bouncing a lot or switching too frequently (insufficient hysteresis) this could maybe be the prob.
This could be just the wild ramblings of a dissorientated cat...what da ya think guys?

Del

There has been a huge amount of great input on this - and as some have said...

ARGH - too many variables...but everything was covered here

Cartman - i hope you get this fixed 'cause Hot Water is Good Stuff !

Best of Luck

I have a similar problem.

My electric hot water tank stopped working a few days ago. After a bit of internet research, I replaced the top heating element and got hot water for a few hours, but now it's cold again.

I purged the tank of air before turning it back on, the inflow of cold water is fine, I replaced the element with the same 3000w 240v element.

Is this a problem with my wiring perhaps? The breaker box in line before my water heater has some black corrosion around the negative lead - kinda looks like oil sludge.

Check your non return valve.

Hi im late in this but just wanted to say i work with a plumbing heating contractor. We had similar issue with a hotwater heater issue in beauty salon. First off like otgers keep it simple and eleminate esady causes. 1 check for proper voltage at top incoming . Our was 208/240 elements and we had 209 v incoming and had 4500/3500 elements. If u had only 120 volts at 4500 watts u have a amp reading of around 38 amps. If u had 240volts at 4500 u see a reading around 17 amps.if it was a overload or short the breaker trip or fuse blown. I agree with watr not sumerging element. If water got to hot the hi temp trop buton on stat on top element trips. So then i look for water isdue is water sumerging element.or bad design elements. This is my input. I have seen shotred elements in bottom tanks dure to sedement build up around elements causing shorting and burn out Hope this helps.