How to test electric water heater?

A few months ago I replaced both heating elements in our electric water heater. I checked the dip tube at the same time, and it was OK. (Thanks to the people here who helped.)

Now for the last couple of weeks sometimes there is plenty of hot water for bath/shower and sometimes not. There either is or isn't - with not much in between. This is NOT right after using hot water for washing dishes or clothes.

I have a volt/ohm/amp meter, but I don't know how to test these A/C things. How can I (with only a little experience) test the water heater elements and thermostat?

Thanks in advance.

Reply to
Jud McCranie
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Sounds like your thermostats are acting up. Heaters either are good or they aren't, but the thermostats can cause the problems your reporting. =

Reply to
Geoman

They are probably as old as the house - 7 years. Is there a way I can test them, or should I replace them?

Reply to
Jud McCranie

I hope you know unless you have subsidised Hydro Gas is 50 % cheaper. thats a BIG savings. Piss on the waste

Reply to
m Ransley

Yes, but there is no natural gas line here. I guess I could put in a tank and change appliances, but it would probably take a long time to pay off.

Reply to
Jud McCranie

Jud,

Be careful while you do this : Snap the jaws of the ammeter around one of the wires that goes to the top element. Then...turn the top thermostat up as high as it will go. You should get a reading. THen, turn the upper thermostat to its lowest setting -- you should see the reading drop out. (leave it at this setting while you test the bottom element now )

Snap the jaws on the lower element. Then, turn the lower thermostat to its highest setting. You should get a reading. Then...turn the lower thermostat back to where it was.

Then,..return the 'upper' thermostat to where it was.

If both elements are working, then, you are either depleting the hot water which then turns to cold ...which means you need to allow more time for recovery in between usages. AND/OR...you have alot of sediment in the tank which is making the tank heat up slower.

Be careful when working around electricity. If you fry yourself...i hope to see you in heaven one day if you know The Lord personally.

Dave

Reply to
HVAC IsFun

In the fine newsgroup "alt.home.repair", Jud McCranie artfully composed this message within on 07 Jun

2004:

My electric water heater is as old as the house - 15 years old - and is just now starting to exhibit signs of aging. It will start to cool off after a single shower so I'm planning on replacing it and not worry about trying to replace heating elements. This is the same for any appliances in my home that go bad. They make them so much more efficient these days.

Reply to
Cheryl

I forgot to mention that I don't have the "jaws" type of meter. My meter is the kind with the two leads. Can it be done with that type of meter? (I know how to be safe.)

Reply to
Jud McCranie

Sounds like a good plan if you don't like to mess with things. But many new electric appliances are no more efficient that 15 year old ones. Examples, water heater, stove, fans, incandescent and fluorescent light, etc. Improved efficiency will be most evident in refrigeration equipment, i.e., refrigerators and ACs.

Reply to
George E. Cawthon

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Reply to
Robert Barr

In the fine newsgroup "alt.home.repair", "George E. Cawthon" artfully composed this message within on 07 Jun 2004:

Thanks for pointing that out. I guess I'm just a "don't like to mess with things kinda gal". I like the features I read/know about things like stoves (self cleaning; mine isn't) but I didn't know water heaters haven't changed. The plumber who looked at mine said the problems were just "age". 15 years old. He wasn't even trying to sell me one since he doesn't do hot water heaters anymore. I'm starting to think that a 11-15 year old house is not the right age to buy one. Everything is "getting old" that was in there from new.

Reply to
Cheryl

George,

I believe the water heater also has some improve such as the insulator so it may reduce energy cost if you live in the cold area.

Reply to
Hai Pham

Reply to
George E. Cawthon

No. The "two leads" will measure just about anything except AC amperage.

Reply to
Stormin Mormon

'I forgot to mention that I don't have the "jaws" type of meter. My meter is the kind with the two leads. Can it be done with that type of meter? (I know how to be safe.)

Reply to
HVAC IsFun

Umm...yes you can...since you know so much, you might want to tell UEI, and Fluke that they are mistaken on the instructions that come with the standard DMM.

Umm...no. Wrong again Dave...that wont tell him anything, and depending on how the units wired, he will have voltage AT the elements at all times. You dont really work in the trade now do you?

Reply to
CBHVAC

A device that has an encased coil of resistive wire that gets hot when electricity is applied is pretty basic. If it takes 1500 watts to heat your water, that means you are using 1500 watts of electricity. You CAN NOT make heating coils more efficient. If you cut down to (example), 1000 watts, all you are doing is making the heater run longer, and create hot water slower. In other words, there is NO SUCH THING as "more efficient" when it comes to devices that heat using electric. Of course the advertisers do a great job of marketing to make you BELIEVE that the new devices are saving power. It's advertising, and that's all it is. The only way to make a water heater more efficient, is to make the insulation better surrounding the tank. If you think your insulation is poor, why replace the tank when a $10 water heater blanket can be purchased and installed in minutes using a scissors and duct tape.

It's different with motorized appliances, and cooling appliances. There are ways to make them more efficient (not that they really do it). For example, My 1990's refrigerator died last year. I acquired an old 1940's refrigerator for free. It still runs, is quieter, and my electric bill dropped about 10%. I was going to buy a newer fridge, but why..... I got a new door gasket for a few bucks and other than the fact that I have to manually defrost the freezer, I have no complaints.

The bottom line. Most of the "more efficient" advertising, is nothing more than marketing to make sales.

Reply to
spamfree

'Hi HVAC, hope you are having a nice day '

ME: Ill let you know after the day starts.

If the HO gets voltage at the element , then he can "shut off the power" to the water heater and feel the tank (right next to the element) with his hand to see if its hot; if it is then its fine.

Will you be having a nice day today #2 ???!

Reply to
HVAC IsFun

According to CBHVAC :

I think this is a matter of interpretation. You cannot test amperage with a two lead meter _unless_ you interrupt the circuit and place the meter in series with the load. Which is what everybody tries to avoid. Hence clamp-on meters etc.

Secondly, many DMMs can't do AC amps high enough anyway. Especially the units that most DIYers buy from Radio Shack et. al.

For example, mine's limited to 10A DC, and you have to move the test probes to different plugs on the meter. Doesn't do AC amps above 1A.

If I had to make one AC amp measurement, I'd stick in a shunt resister and measure the AC voltage across it.

Ie: If you stick a .01 ohm resister in series with the load and measure the voltage across it, you'll get .01 AC volts per AC amp. With a .1 ohm, you get .1 AC volts per AC amp.

[Do take into account power dissipation of the resistor. Running 10A across a .1 ohm resister means you have to use at least a 10W resistor. With a .01 ohm resistor, it only needs to be 1W.]

If I had to do a lot, I'd buy a clampon ammeter. Don't have to disturb the circuit at all.

Reply to
Chris Lewis

There's a switch setting labeled "AC mA" with a ~ under it, for AC. Does that mean that it can measure something in the miliamp range, but not higher?

Reply to
Jud McCranie

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