Water heater on electric

Blkbart · 07-03-2020, 01:34 PM

Hello all,
Very frustrated, just finished installing a new water heater in my 2003 Itasca Horizon 34HD. One of the primary reasons I replaced it was the lack of 120V AC heating ;-(. Did notice that the amp draw is only 1 to 2 amps which obviously way too low for the heating element to be working. I did a switch check on the AC leads when the switch is on, full 120V. What might you guys suspect is the issue? Is there a breaker I need to check?
Thanks,
Bart

Morich · 07-03-2020, 02:58 PM

Did a drawing check( since you got us all the info needed!) and it looks kind of straight forward except for a load shedder that I'm not too up on how it works, other than the idea being it cuts off parts of the load when things get close to full use. I marked the things I thought were important to check and it looks like it is a straight run from a breaker to the load shedder and then to the heater.
If I understand you are getting full 120 at the switch when turned on. Is that on both sides of the switch, 120 coming in and when turned on 120 on the out side as well? Should be correct and mean the power is getting through the breaker, through the load shedder and heading to the heater.
That leaves very little it seems other than making sure the 120 wiring at the heater is correct and any board, etc. is okay but also make sure there is a good ground to make the full circle for power back to the AC panel neutral.
BAH! Sometimes these pictures come out good and sometimes almost too weak to see! Mostly it shows if you have power at both sides of the switch, all the rest is okay up to that point! something on toward the heater is not getting it done. Might check wiring and look at it there on the heater itself. No other complications involved.
Can you see wiring that goes to the heating element itself? That would likely be kind of heavy wire to check that power is going directly into the heating element. If you can see 120 going in and then check it coming out, the element is good and you need to check it has a good ground.
If you see it going in but not on the other side coming out, the element seems open/bad.

l1v3fr33ord1 · 07-03-2020, 07:03 PM

Bart-

Here is a link to posts by "Old-Biscuit" on iRV2, about water electric testing, both Atwood and Suburban. If you read through a couple dozen you'll have several things to check, and how to check them.

al1florida · 07-04-2020, 07:27 AM

"If" you happened to turn on the electric side of the water heater and you did not have the water heater tank full of water, you probably burned out the heater element.

Blkbart · 07-04-2020, 09:56 AM

Morich,
Thanks so much for the information and advice. Going to check it all out today. Would running a jumper ground to the chassis be a test option?
Thanks,
Bart

Blkbart · 07-04-2020, 10:02 AM

Thanks for the link! Getting a lot of information! New test idea, Can I wire directly to the 110V leads on the back of the water heater with a 3 prong extension cord?

Blkbart · 07-04-2020, 10:10 AM

Just talked to a knowledgeable friend who said most definitely DON'T ground to the chassis!

Morich · 07-04-2020, 11:28 AM

Since you were able to check amp draw, do you have a voltmeter to test for 120AC?
If it is on hand and one can find the leads to the heating element, using the meter with one probe on ground and the other to one end of the element to see 120 going in and then the other wire to see 120 coming out, it proves the element is good. then the question would be why that 120 is not getting back to neutral.
But if you put one probe on one wire and see 120 going in but not when touching the other wire, it means the element is broken or we call it open.
AC is just a lot like DC when we look for how it makes things work. It has to come out of the supply, through whatever we want to work and then get back to the supply to make a full circle. So when we are chasing a problem with a voltmeter, if we see it gets to one point and then it doesn't get to the next point----there's a hole in the road! The element is kind of like a big wire that heats if we run AC through it and they can break.
The problem with using a ground to the frame is that puts 120 AC on the frame and all kinds of things which are likely to shock you or not be good for 12 volt DC things that do use the frame as ground. Kind of a techie difference on ground and neutral wires as they both go back to the same point in the breaker boxes but we really want the AC current to stay on the neutral, not the frame ground.

jerichorick · 07-09-2020, 11:33 AM

Quote:

Originally Posted by Blkbart

Hello all,
Very frustrated, just finished installing a new water heater in my 2003 Itasca Horizon 34HD. One of the primary reasons I replaced it was the lack of 120V AC heating ;-(. Did notice that the amp draw is only 1 to 2 amps which obviously way too low for the heating element to be working. I did a switch check on the AC leads when the switch is on, full 120V. What might you guys suspect is the issue? Is there a breaker I need to check?
Thanks,
Bart

Remove the leads on the element WITH THE BREAKER OFF and use your ohm meter to measure the resistance of the element. You should see a fairly low resistance. I don't have the value off the top of my head.

jim46 · 09-04-2020, 11:45 PM

I am also experiencing tepid water temperature from my water heater while in electric mode. I just purchased the new trailer one week ago. Everything seemed fine during PDI. The water was hot before delivery. During our trial run at home I was able to get very hot water while in LP gas mode; however, not while in electric mode. I will follow the suggestions in this thread and maybe I can find the problem. I'm a newbie, so wish me luck!

danhannah · 09-05-2020, 01:45 AM

The water heater is usually lowest priority for a load shedder. In my rig, if I turn on the Microwave, the water heater shuts off - Microwave has priority.

If no other tests work, try unplugging the microwave, or better yet, bypass the load shedder completely to check if it is the problem.

jim46 · 09-06-2020, 11:28 AM

danhannah, thanks for the quick reply to my comment. I have read other forums and watched several YouTube videos. Since the LP half of the water heater is working fine, now I understand I must concentrate on the back of the Dometic/Atwood heater, where the electric heating element is located. I have turned the circuit breaker on and off several times. Also, I can hear the relay "click" on a second or two after I toggle the electric switch to the on position. Now I will go out and access the heating element to see if I can find any loose wires. I doubt the element could be bad since it is new and I did not turn on the electrical without water in the heater.

Morich · 09-06-2020, 11:34 AM

Be aware that the electrical heating will happen much slower that the gas heating.

jim46 · 09-06-2020, 11:42 AM

Thanks, Morich. I guess I need all the help I can get. Yesterday I had it on for five hours and no warm water. I will let you guys know what I find.

**creativepart** · 09-06-2020, 12:45 PM

Quote:

Originally Posted by danhannah

The water heater is usually lowest priority for a load shedder. In my rig, if I turn on the Microwave, the water heater shuts off - Microwave has priority.

If no other tests work, try unplugging the microwave, or better yet, bypass the load shedder completely to check if it is the problem.

Dan, Jim46 has a travel trailer and I've yet to see a Power Control System in a travel trailer or any other system that "sheds loads" like we have in our Class A motorhomes. So, I doubt that unplugging the microwave would have any effect for Jim's problem.

Goodspike · 09-06-2020, 01:45 PM

On the topic of propane vs. gasoline, I had a two day trip last week where the refrigerator ran for 3 days on propane, I used the stove for maybe 15-20 minutes, and I used the propane water heater occasionally, and for 3 showers. When I got home I couldn't tell which of the two tanks I was using by lifting them--although I could probably tell if I got a scale out. Point being, I don't think it probably costs a ton to use the propane water heater.

FWIW though, I don't leave it turned on. I'll let it heat up and then shut it off, either when it shuts itself off (water hot) or before then. The water will stay warm for hand washing quite some time--even overnight.

jim46 · 09-13-2020, 11:15 PM

I have not found the solution to my water heater (electric not working). We have been planning our first trip with our new Micro Minnie beginning tomorrow. I thought propane would get us by. Now I found out that the coach battery has not been charging while plugged into 110 next to the garage, so I charged it with my own battery charger. The 110 outlets do work in the trailer, but I guess that doesn't mean everything works....to my chagrin

Yes, I know I should not have spent so much time working on the water heater problem, but I didn't realize there is a broader problem. I guess I should have reserved electric campsites. Wish us luck. Jim

Goodspike · 09-14-2020, 07:41 AM

I would check your various fuses and breakers, including the 12 volt fuses. On mine most the 12 volt fuses have an LED above them that lights when the fuse is blown.

jim46 · 09-14-2020, 07:49 AM

Thanks for the response, Goodspike. I have not noticed an LED indicator light on my fuses. I will go out and check again now.

jim46 · 10-02-2020, 04:19 PM

Final answer to my dilemma in previous comments.....Two 40 amp fuses were blown; therefore, shore power could not charge my battery. Goodspike was right on. And why wouldn't the water heater work on electric? It wasn't plugged in. That seemed strange to me until I realized it probably was left unplugged so no one would inadvertently activate the switch with no water in the tank. I would like to take credit for finding the problems, but thanks to my dealer (Lazydays - Minneapolis) Ryan, my tech scheduler arranged a "quick look" and an electrical technician found both issues. Thanks to all who provided excellent comments. By the way, my wife and I thoroughly enjoyed our first RV trip with our new little Winnebago Micro Minnie......what fun!