Electric HWH tripped off. ???

[Roy Starrin]

I have an 8 year-old Bradford White 50-gallon electric HWH that stopped functioning. Since it had a 6 year warranty, I figured it had simply outlived its useful life, but wanted at least to check it out. As I traced out its circuits I found that immediately above the upper element (dual 4500 watt elements) was a small electrical distribution block which had a reset button. I pushed, it clicked and it began heating. Has worked fine overnight. I am not aware of any household electrical surges, glitches, etc. which might have caused it to trip, nor do I know what it is supposed to be protecting against. Anyone with a SWAG as to why it's there, what might have set it off,and if it is a matter of concern. If it matters, I did have it wrapped with a blanket. Could it get too hot? If it trips again, will probably replace it. In looking at those in the big box stores (GE) is there any to avoid or recommended? (WIll probably get whatever I want and bring it home, then call a plumber to install it) They are sold with various warranties (6, 9, 12 years or even "forever") Since each costs more, it seems more like a an insurance gamble on the part of the mfgr who probably believes it is worth the gamble. Any thoughts on the increased warranties-increased price aspect. Thanks in advance for any help.

[RBM]

That red button thingy is a bi-metal high temperature cutout device, with manual reset. Your heater overheated, so it popped. You may have a bad thermostat in the unit

[avid_hiker]

Roy Starrin wrote: I am not aware of any household

Water level .........which if low....then the top element would trip it..overheats. You might want to drain/flush out the tank and get nay/if any sand or slug buildup that may have accumilated over the years. If there is alot of sand....then your bottom element would be heating the sand.....and not the water which will also trip it. Start with a good flush of the tank......and go from there.

If you dont know how........hook up a garden hose to the valve at the bottom of tank. Run hose outside and then turn the valve on. Note........be sure that the water heater's power is OFF before you do this. Good luck.

[Jeff Wisnia]

avid_hiker wrote: If there is alot of sand....then your bottom element would be

Please explain the physics behind that one.

Thanks,

Jeff

[avid_hiker]

Physics.dont rightly know........only know that with a previous e.water heater I owned ( water being well water ), that the tank was filled half way with sand and causing the heater to over heat............like in this case. In my understanding is that the bottom element actually heats up the water initially, where as the top element maintains the water's heat to the desired temp.

In the problem I had........after flushing the tank out.....this fixed the problem I had. Physics, well, dont rightly know......Id be guessing.........but for a guess.........my guess is that the bottom element , which kicks in to initially heat the water, was covered with sand.....and the heat conducted from the sand to water was not quick enough, therefore the bottom element stayed on and overheated ( the sand ) which tripped the ckt. Does this sound like a good guess? :-)

[terry]

. Just because something is a couple of years beyond its guarantee it shouldn't be considered worn out?

Also it would appear that the OP is not familiar with an overheat switch; which are common in quite a few appliances! (Clothes dryers, microwaves, etc.)

Also it sounds as though no follow up maintenance (i.e. flushing out of sludge) has been done on a six year old hot water tank installation! About time!

No wonder we become a 'throw away society'!

As others point out something caused that overheat switch to trip, maybe low water level? A thermostat that is old or sticking so that temperature overshot? Or the bi-metallic overheat itself is a little tired?

Even a complete new thermostat with overheat is not expensive especially compared to having the whole tank replaced.

[Jeff Wisnia]

I don't disbelieve what you saw happening, and I think I may have an idea why that much sand that could cause the overtemp thermostat to trip. The overtemp is located right next to the upper thermostat and does it's thing when the temperature at that location exceeds its operating point.

If I had to make an informed guess I'd say that the sand thermally insulated the lower thermostat from the actual water temperature enough so, as you said, the lower heating element stayed on longer than it normally would have, which was enough to heat the water to a temperature above the overtemp thermostat's setting and cause it to trip.

Jeff

[hallerb]

just be prepared the drain valve may not open or will break when it does, or not close or drip afterwards.

be ready to replace the valve and have plenty of time to do so espically if the valve is plastic, they are basically one use drain tank at end of life........

[Don Young]

Be aware that some thermostats only open one of the hot lines to the element. If the element has melted or corroded thru, current can flow from one hot line thru the water to the ground. This will heat the water very slowly but will continue to heat when the thermostat opens. This sometimes causes the heater to overheat when no hot water is being used, such as overnight. Just something else to check.

Don Young

[mm]

I believe if the water doesn't cover the element, the element will always burn out. Since pushing the red button at the top caused it to start heating again, I don't think the water level was low.

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Well, according to the original post, it was the red button at the top, which controls the upper element afaik, that tripped, so this paragraph and the one below might be of value to someone else, but I don't think the OP should start here.

OP, do you have a red button on the lower element, as well? I'm not absolutely positive every one does, but I think that the heat limit switches are thermomechanical and can't trip anywhere near quickly enough if a heating element two feet further down overheats.

[mm]

Yes, it should. Automobiles that come with a 5-year guarantee should be scrapped when they break down after 5 years.

>

[Roy Starrin]

This is the OP: The button is in a little block on top of (and I think intergral with) the upper thermostat. According to the wiring diagram inside the upper cover, it controls power to both thermostats. WRT other comments. I am aware of the drain-clean-leak forever cycle of the bottom valve (in my case plastic) and have a cap to screw on it when/if it leaks. The HWH is functioning normally since reset. Since it is no longer wrapped, I wonder if it just got extra hot, especially because it is fed by the output of the tankless coil in my heating boiler. Anyhoo, the plumbing circuit is set up that I can cut out the HWH and just use the tankless coil (boiler is on 110, so if I have to go on a generator, I can still have hot water), so I think I'll just wait and see what happens. Thanks to all for your input. Still would like some input on better/best HWH. In my research I've found a whole page on how bad the the Whirpool sold by Lowes is. I also noticed that every dimension/specification of the 6/9/12 year GE tank sold by HD that I would use is exactly the same; the only variable is the increasing price. To me this sort of confirms that the extra money is simply an insurance premium for the same product.