Electric Water Heater Problem, Repair or Buy new, please help

[Robert]

Hi All:

I have a problem with my electric water heater, which is 66 gallons, Sears brand, 13 years old.

We bought this house about six months ago. Yesterday, without any previous symptoms, I found the water from the heater very hot - steaming. Since we were in a hurry to go out, I just switched the heater's circuit breaker on the main board OFF. I thought the thermostat might have gone bad and decided to replace it by myself today.

Today morning, I switched the circuit breaker back ON to get some hot water (generally I don't switch off the heater at all). After an hour or so, since I did not get any hot water, I inspected everything and found that the circuit breaker of the water heater on the main board had tripped.

I searched google.groups and found a lot of information regarding this

- with possible causes, (1) a stuck thermostat OR (2) bad heating elements.

To experiment, I turned the bottom thermostat all the way to the lowest point. Put the upper thermostat at a medium level and switched the circuit breaker back on. Within about 5 minutes the circuit breaker tripped again. I tried the same experiment with the upper thermostat with similar results.

So here are my questions. I think either the thermostat(s) or the heating element(s) had gone bad. (1) Should I get an electrician to repair the heater - replace the thermostats and/or the elements OR (2) Considering the age of the heater (and the previous owner was not good in maintaining it ? she never drained it in a period of 5 years), should I buy a new heater.

Please advice.

Thanks in advance for your time.

Robert

[Des Perado]

Replace the water heater! It has already provided super service and owes you nothing. Get a new one. Des

[Jeff Wisnia]

I assume from reading your post that you haven't yet put in that new thermostat, unless you did it in the middle of the night "today".

The problem you describe would be a cinch for someone with the right test equipment and understanding of "hot water heater electrics" to diagnose. All it takes is an amprobe (current meter) and a voltmeter (if that's not already combined with the amprobe.

Without test equipment you're likely to frustrate yourself stumblig around "blind", which is what you'll be doing if you can't make voltage and current measurements to track down the culprit.

The typical 220-240 volt hot water heater with two elements works this way:

From a "cold" start, current flows through the closed upper thermostat contacts (and the overtemperature cutoff device) to energize the upper heater.

Assuming nobody's pulling hot water from the heater:

When the water in the upper part of the tank reaches the upper thermostat's set point temperature, that thermostat turns off the power to the upper heating element and enegizes the input of the lower thermostat, which will power the lower heating element until the water in the lower part of the tank reaches the setpoint temperature of the lower thermostat.

Fom that point on, the lower thermostat will cycle on and off every once in a while to keep the whole tankfull at a contant temperature.

When hot water is drawn from the heater:

It is taken from the top of the tank, and cold water enters at the bottom of the tank, through a "dip tube" extending down to near the tank bottom from the "cold" inlet fitting at the top.

The lower thermostat will close first, as the entering cold water cools it, and will enegize the lower heater. If hot water continues to be drawn off, the lower heater won't "keep up with it", and cooler water will reach the upper thermostat, causing it to switch over to powering the upper heater again.

If water continues to be drawn it will take heat away faster than the upper heater can keep up with and you "run out of hot water."

(End of narrative.)

I think your best bet is to bite the bullet and have a new hot water heater installed, given the age of your unit.

Otherwise, if you don't have a friend who knows these things and has the right test equipment, you are going to have to find a repairperson with enough smarts and the right test equipment to properly diganse and fix the problem without replacing more parts than are really needed. Sad to say, those aren't the attributes of every plumber you might call. A qualified person's laborcharges, plus the cost of the repair parts he supplies (at "full retail" of course.) makes buying a new heater not such a bad thing to do.

That said, if you happen to be near Zip 01890, I'd come over and give you a hand gratis, just because...

Happy New Year,

Jeff

Robert wrote:

[Mad Mac]

(Personal Opinion) I'd tend to agree with Des here. Given the age of the unit, the money you spend on professional repair would probably be better invested in replacement.

[Chris Lewis]

According to Jeff Wisnia :

I think so too.

This is my reasoning: having both the water overheat _and_ the breaker trip is suggestive that the OP has multiple faults in the heater, and short of having an expert diagnose things, the OP may get himself into real jackpot. Plumbing prices being what they are, hiring a plumber to diagnose and repair the heater will probably cost nearly as much as a new heater.

1) if the water overheated, the thermostat isn't tripping. So, you have fairly good evidence that the T-stat is defective. [At least you noticed this. In some cases (stuck OP valve (they get stuck with age) and a non-return valve in the supply), a failed thermostat can lead to a steam explosion.]

2) If the breaker trips, either something is wrong with an element, or the thermostat is broken to the point of energizing both elements simultaneously, or the breaker has gone defective too.

3) If both elements energize simultaneously, I would _expect_ the breaker to trip faster than 5 minutes. Unless the double element current is only a bit higher than the breaker.

4) It's fairly unusual for an element to draw more current than it should. They usually simply go "open". For an element to draw more current, I would immediately suspect that the element coatings have delaminated, and either the upper element has broken and fallen on the lower, or, something else has fallen on the lower element (eg: a corroded-thru anode).

I personally would expend effort to diagnose the problem[s] before deciding to junk the heater. I hate replacing things when I'm not exactly sure what's wrong.

In your case, I'd suggest:

Energize the unit again, and test for voltage on _both_ elements, using a voltmeter or neon tester. If both elements are energized simultaneously, you've identified the cause of the breaker trip - you already know the thermostat is defective (because of the overheat), this rules out the elements as a cause of the breaker trip.

If both elements energize simultaneously, replace the thermostat.

If the thing is still flakey, get a new tank, and return the T-stat.

[Richard]

Check to see if the last owner kept the extended warranty up on the water heater. Sears loves to call up every couple years and talk you into extending the warranty on what you have purchased.

Plan B: Get a new one.

Richard Houston, Texas

[Ron Hardin]

In 1980 my elec water heater died; I called Sears, they were out the next day (door unlocked, I was at work) and replaced it, no problem. The only problem was they signed me up unasked for the super duper extended warranty. I called and cancelled it. What a rotten deal that would have been.

The unwarranted water heater is still going strong. The sulphur smell ended after a year, after the anode rod burned through I guess.

[Jeff Wisnia]

But, do those warranties transfer to a subsequent owner?

The OP said he bought the place 6 months ago..

Jeff

-- Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"If you can keep smiling when things go wrong, you've thought of someone to place the blame on."

[Robert]

Hi All:

Thanks a lot to everyone who responded to my question.

I bought a new water heater - not installed it yet.

Special thanks to Chris Lewis and Jeff Wisnia for their detailed replies, which helped me to learn more about water heaters.

Thanks,

[TripFarmer]

IF YOU'VE GOT TO CALL A REPAIR PERSON AND IT'S 13 YEARS OLD and you're intending on staying there a while, you'll be better off putting a new more efficient one in.

Trip

[George E. Cawthon]