solved- 378TS elect water heater mystery

Nomore9-5 · 03-29-2013, 12:43 PM

I have a mystery on my hands. Have 120v at HWH breaker ( phase -neutral) nothing @ load or line side of hi limit/ thermosat, nothing at line side of WH switch. Is it that I'm not measuring right ? For switch I put 1 lead of tester into wires coming to switch ( did both in case in case I had wire going to HL/ Stat and not breaker ) the other on water heater casing ( ground?)- nothing. For H/L Stat again 1 lead on line side ( and just in case load side ) the other on water heater tank again nothing.
Can anyone out there tell me if I'm doing this right . Frankly I'm concerned - if I'm doing it right this could mean a broken wire between breaker and water heater and if that's the case the breaker should've tripped

Thanks

Iggy · 03-29-2013, 12:58 PM

Did you turn on the switch in the lower left hand corner of the hot water heater? (outside) see picture. This must be on to run off electric.

Please take a look before I say anymore.

You also failed to tell us what year and model Georgetown you have.
You also may have a swtich inside on the control panel you need to turn on electric.

Nomore9-5 · 03-29-2013, 03:15 PM

Actualy I removed the wire leads from the switch to try to determine if the switch was faulty ( internals of switch broken) there was no sign voltage coming to switch ( as I said I tested both wires connected to switch in case one of them was the wire going on to the hi limit/ stat ) . There's also no other 120v switch like you have inside the coach - only a switch 12v dc control circuit for propane side of water heater
My MH is a 2012 Georgetown Model is a 378TS

Nomore9-5 · 03-29-2013, 03:20 PM

Sorry meant to say only interior switch is for 12vdc control circuit for propane side of water heater Electric heating is switched on and off with outside switch at water heater ( the one you indicated)

Iggy · 03-29-2013, 05:08 PM

Quote:

Originally Posted by Nomore9-5

Sorry meant to say only interior switch is for 12vdc control circuit for propane side of water heater Electric heating is switched on and off with outside switch at water heater ( the one you indicated)

Then the only things I can suggest it turn off the circuit breaker in the bedroom panel then turn back on.
Are you sure you have 120 volts to the motorhome?
Does your microwave work?
If you still don't know it is time to get some help by someone who knows about electricity.

bubbles · 03-30-2013, 05:48 AM

Just a note. Circuit breakers trip because of high current draw. If a circuit breaker load side wire breakes it will only trip if the wire shorts to ground ( max current draw). If the wire breakes and does not short to ground it would be the same as turning off the switch (no circuit breaker pop). Additionally; It could be that the ground return for the heating element could be isolated and therefore the tank would not be a good ground source for voltage checks.

**KyDan** · 03-30-2013, 06:54 AM

Most water heaters are plugged into a receptacle which can be accessed from
the BACK side of the water heater tank.
Open a hatch or remove a panel or do what ever you need to do to access
the rear of your WH. Check for 120 v at that outlet and of course check
to see the WH is firmly plugged in to that outlet.

Check for 120v across the outlet, hot to neutral.
Then just FYI check from hot to tank. You should have voltage both
ways but you must have voltage across the outlet.

bubbles · 03-30-2013, 06:57 AM

If you have 120v at the circuit breaker load side and 0 volts at the switch line side then yes you have an open power wire or wire is not routed correctly.

**KyDan** · 03-30-2013, 07:14 AM

See my previous post-- check for power at the outlet before you go any
further.

bakken · 03-30-2013, 08:01 AM

Quote:

Originally Posted by KyDan

Most water heaters are plugged into a receptacle which can be accessed from
the BACK side of the water heater tank.
Open a hatch or remove a panel or do what ever you need to do to access the rear of your WH. Check for 120 v at that outlet and of course check to see the WH is firmly plugged in to that outlet

I imagine most people laughed at that suggestion, but it ain't funny!
That is exactly what happened with ours. I guess the guy who installed the heater wasn't strong enough to push the plug all the way into the outlet, and it did fall out!

cfsoistman · 03-30-2013, 10:01 AM

Unless FR changed the set up that 10 gallon water heater is hard-wired. One of two possibilities. The wire has come apart at the water heater, I know first hand that the wire nuts can come loose from travel. In my case it was in a junction box for the receptacles. Wires weren't twisted together and eventually, with the load the wire nut became a little toaster and melted away the the plastic, causing the wires to come apart. The other possibilty is it came loose in the electric panel. You could check for continuity through the wire by removing the breaker for the water heater and removing the neutral at the panel, turn the outside water heater switch to on and then check between the black and white wire. Of course you want to do this with the coach unlugged. If everything is good you should have continuity through the element and the wire. If not then the wire has either come apart or broke somewhere along the way from the panel in which case you have to gain access to the water heater compartment. I've included two earlier posts showing the water heater compartment and the wiring problem that may be the same as what you are experiencing. One positive thing is the water heater is on a single feed from the panel and running a new feed wouldn't be too bad. The biggest and most time consumption is getting the water heater panel free from the water heater. It's siliconed big time behind the flange and takes multiple times of cutting with al ong-blade razor knife to get through it.

http://www.forestriverforums.com/for...man-21579.html

http://www.forestriverforums.com/for...res-22820.html

Nomore9-5 · 03-30-2013, 02:06 PM

A great big thank you to everyone who responded.I went back and retested using neutral on water heater element rather than tank as voltage reference. Using that got 120V before and after switch,H/L - Stat and at heater element as well. Bought new one at HD and we are back in business. One word of advice when you're changing the element in addition to shutting of WH breaker I found it a good idea to pull WH fuse on DC side of house panel as well - avoids unexpected spark ( I can only assume neutral on water heater must also somehow act as ref for dc as well)

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