Nuisance electric water heater over temp trip

[JerryR]

http://www.grainger.com/Grainger/VUL...&cm_vc=IDPRRZ1 ...Thats a real water thermostat. Double pole switch, as the sacred UL should require on all water heaters.
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Coming from a European and industrial control background, I could never imagine switching one line of a 240v circuit. But the MFG's save 6 cents per unit and thus have made 900 million dollars in the past many years.

Imagine this as true, because it is. That is what everyone has been trying to tell you all along. Perhaps now you will believe it.

See, anyone can learn something new almost every day, no matter how much one thinks he/she knows it all.

Single Pole Thermostats and are used in dual element GE, Rheem, Ruud, Richmond, AO Smith, American, GSW and Whirlpool heaters AND they meet UL- and CSA listed code.

I would really like to see a picture of the thermostat in your double element water heater where it is a Double pole device. Is this an Industrial or European water heater or were you just mistaken?

[ballvalve]

I tested an old ray pac commercial, and it has a control box with relays. Now I know that cost is an issue for residences, but we both know a life is worth a little more than a double pole switch. I assumed that engineers would care about the safety at the residential elements.

Would you install a 240 circuit breaker without the connection between handles so that one line would remain hot? I see a sweet deal from UL to the waterheater guys so that they can make them in mexico of tin cans and up the profit so that the "head" of GE can take home a few billion a year. Nice to have 22 vacation homes for the sake of a 6 cent killer switch.

Ethical bankruptcy. Hey: send it to China, then no liability need apply.

[jadnashua]

A WH should not be worked on unless you remove power to it...one shouldn't assume it is safe if the thing isn't calling for heat. Same is true with your furnace - it's ready to go - power running around inside, just waiting for the thermostat to call it into action. IOW, it is a system, it works fine, just don't muck around inside unless you know what you are doing. Under normal circumstances, it is totally safe until you take the safety covers off - THEN, you better know what you are doing. Same thing is true with almost anything electric or electronic...it's safe until you break it open.

Even older table lamps with screw-in bulbs that didn't have a polarized plug could kill you when replacing a bulb if you happend to do things just so.

There's a reason why there are safety warnings on electrical appliances...read and heed.

[JerryR]

A WH should not be worked on unless you remove power to it...one shouldn't assume it is safe if the thing isn't calling for heat. Same is true with your furnace - it's ready to go - power running around inside, just waiting for the thermostat to call it into action. IOW, it is a system, it works fine, just don't muck around inside unless you know what you are doing. Under normal circumstances, it is totally safe until you take the safety covers off - THEN, you better know what you are doing. Same thing is true with almost anything electric or electronic...it's safe until you break it open.

Even older table lamps with screw-in bulbs that didn't have a polarized plug could kill you when replacing a bulb if you happend to do things just so.

There's a reason why there are safety warnings on electrical appliances...read and heed.

Jim,

BINGO

Before retiring, I managed a service organization. We seviced all kinds of heavy duty equipment. One device had 3 phase 240 Vac 100 amp supply, and as long as the safety covers are installed it was safe electrically. Also we had some 480 volt 100 amp equipment installed which my reps serviced. Remove the covers on any of these devices and you expose yourself to some pretty hefty live contacts, just like a water heater with covers removed.

Electric water heaters have historically been exceptionally safe electrically as they are currently designed and manufactured. Of course this assumes that one understands how they are wired and follows proper servicing guidelines. I just did a quick search and found that in a 4 year period there were 12 electrocution deaths directly related to electric water heaters. I would not be surprised if these all were unqualified people trying to service one with the safety covers removed. Reguardless that is a pretty low number. My other hobby is as a private pilot. In that same time period there were almost 1,500 people killed in the US in private aircraft accidents.

[hj]

A "commercial" water heater with "relays" is a completely different device than the standard one or two element water heaters. The thermostat is STILL a single pole device, but the relay will break ALL the conductors. You are trying to tell us that we have to change the wheels and tires as a unit on our cars, but you are referring to a Bugatti Veryon, NOT a Honda Civic.

[ballvalve]

My hot water heater has a mind of its own.

It used to only happen when we went on vacation but now it's about every three weeks.

The water will get really hot and the over temp safety will trip. I will have to wait for it to cool and then reset. This will go on for five or six days and then stop. It will then work normally for several weeks.

It is a dual element electric.

How do I fix?

to go roundabout, just replace the cheap,reliable, though relatively unsafe controls that lurk inside residential "Yugo" waterheaters. And check your elements to see that they are not leaking power to the water.

[ballvalve]

BINGO

Before retiring, I managed a service organization. We seviced all kinds of heavy duty equipment. One device had 3 phase 240 Vac 100 amp supply, and as long as the safety covers are installed it was safe electrically. Also we had some 480 volt 100 amp equipment installed which my reps serviced. Remove the covers on any of these devices and you expose yourself to some pretty hefty live contacts, just like a water heater with covers removed.

Electric water heaters have historically been exceptionally safe electrically as they are currently designed and manufactured. Of course this assumes that one understands how they are wired and follows proper servicing guidelines. I just did a quick search and found that in a 4 year period there were 12 electrocution deaths directly related to electric water heaters. I would not be surprised if these all were unqualified people trying to service one with the safety covers removed. Reguardless that is a pretty low number. My other hobby is as a private pilot. In that same time period there were almost 1,500 people killed in the US in private aircraft accidents.

Bingo! your 3 phase unit had a relay - 20 to 50 bucks that shut off ALL THREE LINES.

Bingo! your residential yugo water heater is dumbed down SO LOW that they cant add a .5 cent sticker saying : "we are cheap: danger, one line to an element is always hot, even thought its immersed in water" i.e. NO warning label.

Hey - dont drive, dont fly and you upped your odds of dying of a broken hip or alheizemers by 99%. Add a 6 cent double pole switch to cheap water heaters, and you saved at least 10 lives. pretty fair return on investment.

By the by - no one without a death wish opens a metal cover on a 480 volt box without shutting the breaker and wearing approved gloves and garb and a good mat.

[JerryR]

By the by - no one without a death wish opens a metal cover on a 480 volt box without shutting the breaker and wearing approved gloves and garb and a good mat.

We worked on 480 volt devices and removed equipment safety covers all the time without gloves / garb and mats. We just shut off the supply breakers to the devices first, just like you should when working on residential water heaters. If you Understand the circuit and wire diagram and follow proper safety procedures they are all safe.

The only additional safety procedure my reps were required to follow when working on the 480v devices was to install a lockout on the breaker at the breaker panel to prevent a passerby from resetting the breaker by mistake.

Jerry

[hj]

The most accurate tests of a water heater are made with the power ON, but using the proper care around a live circuit.