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Tempic
Mar 6, 2008, 09:54 AM
Also posted this in plumbing since I'm not certain where the problem really is - sorry for the duplication:

I have a 7 year old 86 gallon electric water heater that is driving me nuts. It regularly stops heeting the water. I have recently replaced both the elements (twice now) and the thermostats. At first it seems like the problem is solved, but then the same problem occurs.

I'm starting to suspect a power problem. There is a separate breaker box for the water heater, with 2 breakers (30 amp) and on the right side (for the lower element) there are also 2 fuses. The fuses are fine and the breakers don't trip. It is hard to tell for sure because it takes so long the foe water to heat back up, but it seems like flipping the breakers on and off *may* sometimes help.

Any ideas? Do breakers go bad? If they are bad would they trip? I could try replacing the breakers but I don't see a shut off on this separate box so I'm not sure how to do it safely.

donf
Mar 6, 2008, 02:40 PM
This is really a question for plumbing. Plumbers are capable of answering electrical questions for their stuff.

As to your wiring, I need more description than you have provided. Could you please read the label on the tank and let me know what it's requirements are.

What you have is sub panels. But my question is whether they are both live.

They should be sourced by the main panel so I suggest you look there first for a breaker that is tied to one or both sub panel boxes. In your case, there may be two main breakers feeding the subs.

Did you buy this house new? Have3 you ever taken a moment to see how much sediment has built up on the bottom of your tank.

Any way, I going to ask that this item and my post be moved the plumbing forum. They can bounce it back to electrical and lighting forum when they go as far as they can.

massplumber2008
Mar 6, 2008, 03:57 PM
Hi Temppic.

Let's start by asking if you have an electrical tester and do you feel comfortable using it? Can you take voltage readings?

Start by measuring voltage at the breaker and fuses.. work out from there.

Have you tested the fuses for continuity?

Test for voltage at the junction box into heater. You should have 2 separate 110 volt readings (black wire= 120v, red wire= 120v)

Your heater electrical should look a lot like my attached picture... let me know if it is.. ok?

Answer my questions, get back to me with any answers you can provide.

Also, if not comfortable, do not attempt to do this yourself. Electric water heaters are 220 volts supply in so be sure you are careful and confident if doing this yourself. Talk soon... Mark

Tempic
Mar 6, 2008, 04:14 PM
As to your wiring, I need more description than you have provided. Could you please read the label on the tank and let me know what it's requirements are.


Details: Water Heater came from factory with 3800 watt elements upper and lower. It is rated to support up to 5500 on the lower. I installed replacements of 3500 upper and 4500 lower yesterday.

The wiring box is separate from the house wiring. It is hooked to a separate "time of day" meter. The box says it supports 30/30 amps, 155-250 volts. I will try to attach a picture. I don't see any shut off - which makes me nervous.

The heater is 7 years old, and I drain the sediment once a year or so. I have completely drained and refilled the tank twice in the last 2 months during element/thermostat replacements trying to solve this problem.

Tempic
Mar 6, 2008, 04:19 PM
Mark,

I don't have a meter, but I can come up with one. The water heater wiring does look just like the double element one in your picture

massplumber2008
Mar 6, 2008, 04:32 PM
Tempic... get the tester... be careful... need to test those fuses (or install new ones just to be sure) and check for voltage at the heater. You may have reduced voltage ANYWHERE between main fuse box and heater.

Lose one leg (110v) and with 80 gallon heater... lose any kind of recovery? That make sense.. Get back to us when you have the tester... ok?

Like DONF said, breakers should be labeled at the main breaker panel... start there.. work out. Also, note that that TIMER of the day could be defective.. so include that in assessment.

The black wires in the picture.. do they run to the heater as well.. If so, where are the fuses? Just wondering.

Tempic
Mar 6, 2008, 05:09 PM
We have lived in this house for 11 years and this is the first time I have opened that box. I didn't remove the fuses. I noticed the difference between the two sides of course. I just figured that since the lower element supports a higher capacity wattage that fuses were needed there that were not needed on the other side. Should I put fuses in there?

massplumber2008
Mar 6, 2008, 05:49 PM
Do not put fuses in left side. First see what voltage reading you are getting at the heater junction box. If both legs read at 120 volt or so... then heater is powered fine and NO additional fuses needed... but need that meter first.

BUT, for fun...do those black wires (without fuses) show up at the water heater junction box...? Chase this out... Let us know. This is simpler then it appears... BUT still dangerous as can be... Get the meter.. and then let us know you are ready to test. We will work from there ( the timer has raised an eyebrow over here..! ). Goodnight!

Tempic
Mar 6, 2008, 09:27 PM
OK - here's the scoop. I have a neighbor who is an electrician so he came to check it out. Using he meter he discovered a couple things:

* The breaker on the left doesn't do anything
* The left side of the breaker on the right is not working.

So he switched the red wire and the fuse from the left side of the right breaker to the right side of the left breaker.

One of the frustrating things about a water heater is you can't really tell if it is working until the water heats up - so we'll see fi this did the trick. He also recommended that I replace the breaker box and wiring to the heater at some point.

Thanks for your help guys

Tempic
Mar 7, 2008, 06:53 AM
Well - this morning there is no hot water. On the theory that if the breakers and wiring are not in the best shape, I'm going to try replacing the lower element (currently 4500 watts) with 3800. This is the factory configuration, and though the water heater can support more, maybe my electrical system can't.

One curious thing - when the neighbor was testing with his meter, he said the individual lines were delivering 110 volts, but he couldn't get a reading of 220 when he tested across - which didn't make sense to him.

massplumber2008
Mar 7, 2008, 09:42 AM
Hi Tempic:

Your neighbor is an electrician and did not test the entire circuit from head to toe to finally answer all these issues for you? He was confused as to why you were not getting 220-240 volts across both legs of wire?

I got to tell you... that stinks! See.. I can tell you how to test everything, but YOU need to know how to use an electrical tester or half of what I say will just frustrate you... such as switch meter to 750 volts AC to test for 220 volts across both legs, then return tester to 250 volts AC and test for 120 volts across each wire (to ground)... etc.

It is not that I will not talk you through if you really want... but at this point I wanted to tell you that a good electrician can diagnose this problem in under 15 minutes... start through to finish.

He will test the circuit, the timer, the heater junction box, the upper and lower thermostat (upper fires first till satisfied then sends signal to lower thermostat that fires element until that is satisfied and then lower maintains temperature until someone uses enough water that the upper thermostat calls for heat.. and then heats up, etc.) and the upper and lower elements for voltage and resistance (continuity) (Note that both elements will not have power going to them at any one time.. they fire separately)

But he can do this in all about 20 minutes (a service call charge)... then you can decide what to do based on his recommendation.

It is just that this is soooooo simple for an experienced guy... I just hate to see you working so hard and coming up empty each time... LIKE REPLACING THAT LOWER ELEMENT AGAIN WITHOUT TESTING OR KNOWING ANYTHING BUT A GUESS.

Look, like I said, I am glad to work through this a step at a time with you... I enjoy doing it... why I am here... to help... I just want you to be safe and not get hurt messing with something that can kill people over maybe a $100 service call... hell a good tester costs $70... ;)

Anyway, get back to me... Mark

You decide.. ok?

YOUR wires are fine (from what I see) and they are carrying the correct amps to the heater (2-30 amp fuses... good).

Tempic
Mar 7, 2008, 09:56 AM
BTW - I bought a meter of my own, and after replacing the lower element and refilling the tank I turned the power back on and tested the voltage at both of the elements and they are showing 120. So I'll give it a few hours to heat up to see if this worked.

If I want to test back at the breaker box, what things should I touch the probes to (based on the picture above?)

Mark - I posted this before seeing your last comments.

He did test everything - the breaker box, a junction box just near the water heater, the heater connections, and the elements. That's how he figured out that one of the wires was dead (due to a problem with the left side of the right breaker). Then he switched one wire over the other breaker and retested at each point to see that it was alive.

Both elements won't have power going to them at the same time? That's not what I am seeing with the meter. Touching black to ground and red to the connections on the element I am seeing about 120 volts going to both (with the Sperry meter set to the 600 setting (it has 600 and 200)

massplumber2008
Mar 7, 2008, 10:11 AM
Hi Tempic... OK... but even if you are reading 120 volts (should read 220-240 volts) then something is still wrong.

Set volt meter to 750 volts AC, then test the two wires coming into the heater junction box... should be getting 220 volts.

When element fires, should get 220 volts (meter at 750 volts AC... touch a lead to each screw on element)... make sure thermostat is calling for heat by turning the thermostat above the setting it is at for now (REMEMBER TO LOWER THIS BACK TO SAFE TEMP). If no 220 volts then 1 leg is not powered and needs to be chased back to find out where fault is... can be anywhere from thermosta, back up to junction box, back to timer, back to fuse box, etc... see?

Back at the box, set meter to 250 volts AC and then test the screws one at a time... here, touch one probe to screw above fuse, for example, and other lead to ground (box)... should read 110-120 volts. That would show power in to fuse. Then test screw below fuse same way... touch 1 lead to screw under fuse and other lead to ground (box)... should read 110-120 volts. That would show power out from fuse going to heater and fuse is good. Test both fuses at box this way... then go to heater.

Let me know what you find.

Tempic
Mar 7, 2008, 10:34 AM
Mark - thanks for being so patient

Maybe I didn't buy a good enough meter - it only has 200 and 600 on the ac volts side (200, 20, 2 for dc volts) and then a bunch of options on the ohms side. No 750.

But I set it to 600 and tested the screws at the breaker box above the breaker, and it shows about 120 on each screw. That's as far back as I can test - from there the wires go out the wall to the meter. Does this suggest the problem is the meter?

massplumber2008
Mar 7, 2008, 10:56 AM
At the fuse box, set meter to 200 volts AC... then test

At water heater elements set to 600 volts AC.. then test across both screws at element as instructed at my last post... now what do you get?

donf
Mar 7, 2008, 11:02 AM
Tempic,

I've been following this item since I first had it moved here to plumbing.

I don't follow the electrical side. Personally, I do not understand your electrician friend's statement that he does not know why or how to trace wires back to the source.

Can we start over and allow me to work in tandem with massplumber?

It now sounds to me from all the proceeding posts that you may not be getting the proper voltage across your heating elements. Let's see it that is correct or not.

On all of the heaters I've ever worked on, the electrical wiring went into the top of the tank and were pre-wired by the manufacturer of the tank.

Since you now have a meter (Analog or Digital?) I would like you to make a test at the main splice on the wires coming into the heater after turning the SEP breaker off while installing the meter probes. Connect the Red Probe to the red supply lead and the black probed clipped to the black supply.

Turn the main panel breaker back on, what Voltage level does your meter see, 120 VAC or 240 VAC?

What is the make and model of the heater, who is the manufacturer? Do you have the original instruction book and if so, can you fax the electrical information from the manual to me at (757) 491-5023. And then send me a note to go get it. I'm sill on bed rest and my office is at the other end of the house.

Tempic
Mar 7, 2008, 11:06 AM
At fuse box, set to 200, black to ground, red to screw, gives 120v at each screw

At heater, set to 600, black to screw, red to screw gives me 0
Black to ground, red to screw gives me 120v

massplumber2008
Mar 7, 2008, 11:09 AM
YUP... sounds like power is down at one leg... Do what Donf and I suggested earlier... test power into heater at the junction box on top!

Tempic
Mar 7, 2008, 11:17 AM
I can test the wires at the junction box (there are 4 sets of wires with wire nuts on the ends, and I can also test the wires at the top of the heater.

Questions: meter setting 600? Black probe to what, red probe to what? BTW I don't have clips - just pointy probes.
What does SEP mean? The breaker box? The 4 sets of wires - there are 2 reds and 2 black, each paired with a thicker sort of cloth covered wire.

massplumber2008
Mar 7, 2008, 11:28 AM
Don was suggesting you remove the fuses while you undo the 2 wire nuts at water heater junction box on top... and since no clips... you will need to install fuses back once you have caps and the 3 wires separated a safe distance apart from each other. Then touch red probe to red wire and black probe to black wire if present. Don't touch ground wires at this point.

Set meter at 600.. then take reading... What is it?

And I just noticed that Don has asked you to send him information by fax if possible.. then leave note here if you want to let him know you did it. DON... we did establish that his setup is like the double thermostat picture I have posted... he said it is exactly what he has... does that help?

Tempic
Mar 7, 2008, 11:34 AM
Can I substitute turning the breakers off for removing the fuses?

Upon closer inspection I see there are 4 sets of wires, 2 red and 2 black. Does it matter which red/black to test? Should I test all the combinations?

massplumber2008
Mar 7, 2008, 11:43 AM
Tempic... you should have 2 sets of wires into water heater junction box.. and a ground wire connecting onto heater by a screw. You should only need to disconnect two wire nuts... then test each pair as they were under the caps.. do not disconnect or touch anything... just pull/twist off caps and then set leads on and test as we instructed.

Tempic
Mar 7, 2008, 11:53 AM
I tested the wires at the junction box. You say I only needed to test 2, but I don't know which two of the 4 to test, so I tested them all.

Testing black probe to black wire and red probe to red wire I got 0 for all combinations. Just as a sanity check I tested ground and wires and got 120.

Tempic
Mar 7, 2008, 11:57 AM
BTW - as far as the sequence, here is the layout:


Outside: Time of Day Meter
Inside: Breaker box, junction box, top of heater, thermostats/elements

What we know so far as I understand it:
At the breaker box we are getting 120v (ground/screw)

At the junction box we are getting 0 (wire/wire) 120v (ground/wire)

At the elements we are getting 120 (ground/screw), 0 (screw/screw)

massplumber2008
Mar 7, 2008, 11:57 AM
I said you needed to remove two electrical nuts (caps) and test the wires under the nuts without disturbing the connection (the wires should be twisted together under these caps... do not disturb) what do you get?

donf
Mar 7, 2008, 11:57 AM
Hey are we all online together?

The reason Massplumber is having set the meter at 600 VAC is to prevent the meter from frying on you.

For example, if you are checking for 120 VAC and the meter is set for a max of 50 VAC, but you hit a 240 VAC line, kiss the meter goodbye.

Always start a couple of clicks above the voltage you are looking for. Once you determine that there is voltage on the line then you can drop the meter level down until it is easiest for you to read.

Okay, Lets start at the "Line In" voltage. Is it two wire (Black / Red) or three wire (Black - Red - White)?

For all we know, neither of the boxes on the side are no longer needed.
Find the primary supply wire. It most likely will be inside conduit and be a "Home Run" back to the SEP. (Service Entry Panel or main panel)

Before you do anything else, find the breaker labeled water heater and turn it off. If you remove the top cover on the panel box be extremley careful. Visually inspect the two breakers that supply power to your water heater.

Once you have the two beakers, I want you to ground the black meter probe on the metal of the panel case. Then put the red probe onto the top of the screw that secures the black wire to the breaker. Now, turn the panel back on, followed by the heater breaker. What voltage do you get? Now move the red probe to the second breaker (red wire ) and tell me what voltage do you get. Last panel test, Touch the rd probe to the red wire and the black probe to the black wire, what voltage do you get.

massplumber2008
Mar 7, 2008, 12:04 PM
Donf at post #17, tempic stated that sequence of electric is as follows:

Outside is a TIME OF DAY METER
Then inside is the FUSE subpanel
Then junction box,
Then water heater junction area
Thermostats
Elements... good luck. Thanks for help.

donf
Mar 7, 2008, 12:04 PM
Please,

Understand, I'm trying to verify that the source voltage is correct. So please do not disconnect any thing just yet.

The four wires are paired as a black / red. One side should be hot and the side of the pair should be zero, if you do not disconnect anything. Lets use one diagnostic path for the time being.

Have you gotten the make, model and s/n of the tank yet? Or faxed me the electrical section pages yet?

massplumber2008
Mar 7, 2008, 12:07 PM
Don and Tempic.. I have to go.. will follow with great interest though.. good luck.

Tempic
Mar 7, 2008, 12:16 PM
Don - I have not disconnected anything (unless taking the wire nuts off at the junction box is considered disconnecting)

This is a Kenmore 153.320892 HT 80 gallon, SN: A02228748

What pages do you want - the specs? The wiring diagram? I could also take pictures of the junction box and heater wiring if that would help. Would this process be easier if I just called you on the phone? I'd be happy to do that if you are willing to talk!

donf
Mar 7, 2008, 12:30 PM
Tempic,

It's a little to soon to chit chat. Let me see if I can find what I need on the web. Pictures would be great, especially of all boxes and wires adjacent to the water tank.

Here's my e-mail so you don't have to do battle with small images.

[email protected]. You don't happen to be in the Norfolk, Va. Beach, Chesapeake area of the world?

Tempic
Mar 7, 2008, 01:15 PM
Tempic,

It's a little to soon to chit chat. Let me see if I can find what I need on the web. Pictures would be great, especially of all boxes and wires adjacent to the water tank.



I'm in Michigan. Here is an updated picture of the breaker box and one of the junction box with the wire nuts off

donf
Mar 7, 2008, 02:07 PM
Tiempic,

Who has been screwing with the fused junction box!

Orig photo showed the black wires separated by two blank fuse holders. Your latest has the bottom right black wire removed and left on the bottom of the panel box, with the red lead from the bottom right terminal panel removed and cross connected to the bottom right terminal of the block.

Are you looking for a way to get bit by the electrical snake! First, if you ever remove a wire nut, cover the bare end with tape, And never cross colors without knowing what you are doing. What that does could put 240 VAC across a 120 VAC Breaker. Bad Idea! Please change that back to its original condition, and please don't get yourself bit while doing it.

Why do you want this tank on a "TOD"meter? A "TOD" meter cuts power to the tank during specific times during the day. If the meter tells you tank to stop heating, then there is nothing you can do until the meter let's go of the tank.

Blocking this out says that you have an outdoor SEP. The Utility Meter connects to your SEP. A breaker from the SEP connects to the TOD meter which then connects to the overhead junction box which then connects through the Shielded wires to the water heater.

There are at least two failure points your tank has. One the TOD meter. You cold be doing all this testing for no reason if the TOD meter has cut the power to your tank. Next, the feeder circuit to the TOD meter is blown,

Does the TOD meter belong to the home or the Power Company?

I'm going to drop out for a few minutes and see if I can pull up the docs on the web and find out some more info on the TOD meter.

Don

Tempic
Mar 7, 2008, 02:27 PM
Don,

I explained why the breaker box wiring was changed in an earlier post. A neighbor who is an electrician determined that the left side of the right breaker was not working, and that the left breaker was no even being used. So he moved the red wire over.

The TOD meter was here when we bought the house. I suppose the reason people get them is that you get a better rate since they can turn it off? Not sure. By the way - there is no meter between the breaker box and the junction. Outside the house there are two meters - the one for the rest of the house, and the TOD meter. From there the wire goes into the breaker box, then to the junction box which is right over the heater, then down to the heater.

If they turn it off, would any juice be flowing through to the elements? If the meter shows 120 (ground/screw) but shows 0 (screw/screw) what does that mean? And the last test on the wires shows basically the same: 0 (wire/wire) 120 (ground/wire).

I placed a service call with the electric company to come take a look at the meter since we are heading into the weekend. So I should know in the next couple hours if the meter is good or not.

donf
Mar 7, 2008, 02:31 PM
Okay,

First I had the implementation of the TOD meter. As it is defined in one of my manuals, the TOD meter is more of gagdet used by the utitilies to set varying rates by the different time of day.

Off to check the manual out.

Sorry your not located a tad closer, I was going to drop over for coffee.

donf
Mar 7, 2008, 02:37 PM
Your friend did not do you a favor especially since he just let a bare conductor sit on top of a bare metal box.

Would you please set the wires and fuses back where they originally were.

Have you had a chance to check the main panel for the water heater breakers?

donf
Mar 7, 2008, 03:10 PM
Geese,

The Kenmore site has no record of the "153.320892 HT 60 Gallon" tank.

Is there a model Name rather than a number for the tank. I haven't run into so many obstructions, twists, turns and flat stone walls since I was a rookie.

Electrically speaking, there should only be one supply source of 240 VAC, going into the tanks top. At the top of the tank, you should connect to the blacks and reds using wire nuts. In theory, this would only require one Black pigtail. (Feeder Black, upper element Black and lower element Black) On the red side again one pigtail (Feeder Red, Upper element Red and lower element Red). That's it.

Each element uses a 240 VAC. Black supplies 120 and Red supplies the other 120 VAC. Why are there external boxes? Why are they not configured properly?

Please fax or e-mail me with info on anything the manual has to say about electrical for this tank.

Obviously you are losing power to one side of the element, but which one and why? I'm hooked now!

donf
Mar 7, 2008, 03:25 PM
Were you the one to remove the fuses from the black block of the fuse panel?

I was studying the differences fuse panel picture. If you place the Red probe on one of the lower red leads and the Black probe on either a bare ground wire do you get 120 VAC?

Next make the same test on the Black side, Two of the four wires attached to the block should be hot. Which 2?

Maybe a previous owner intentionally removed the fuses believing he was conserving energy? It's dumb, but it might be that simple.

Tempic
Mar 7, 2008, 03:38 PM
BINGO!!

The utility company guy stopped by. The remote control box for the TOD meter was faulty and only 120v was coming into the house.

But he also said the way my neighbor rewired is no good - needs to be put back the way it was.

massplumber2008
Mar 7, 2008, 03:41 PM
I was wondering about the TOD meter as well guys... but had so much trouble getting any readings I understood... I could not advise best!

Glad you are all set Tempic... and Don... Thank you for following through. Take care all.

Tempic
Mar 7, 2008, 03:54 PM
Thanks indeed! What a great learning experience! Once it is all working again I'm going to go back through all the connection points with the meter so I know what normal is supposed to look like.

massplumber2008
Mar 7, 2008, 03:55 PM
You be careful tempic... and shoot the neighbor! ;) Take care

Tempic
Mar 7, 2008, 05:16 PM
I checked with the neighbor just to make sure he didn't switch the wires in the junction box or the heater (I didn't think he did since he thought he solved the problem at the breaker box - but I wanted to be sure)

So I switched the red wire and the fuse back to the other breaker, flipped the breakers back on and immediately heard the heater kick on. YIPEE!

I put the meter on the upper element screws and got right around 240v. Then I tried the bottom and got 0, but I remembered what Mark said:



The upper and lower thermostat (upper fires first till satisfied then sends signal to lower thermostat that fires element until that is satisfied and then lower maintains temperature until someone uses enough water that the upper thermostat calls for heat..and then heats up, etc.) and the upper and lower elements for voltage and resistance (continuity) (Note that both elements will not have power going to them at any one time..they fire separately)


That is good info - and makes sense now that I understand a bit more.

Many thanks guys.

massplumber2008
Mar 7, 2008, 05:19 PM
TEMPIC... you just said the words I have been waiting to hear all day... 240 volts (or so) across the element... LOL. Take care pal!

donf
Mar 8, 2008, 05:41 AM
Tempic,

I'd like to thank you for this bug, but I won't. :)

Enjoy the hot water, now that winter is almost over! :)