Water heater tripping breaker in older Cypress

[rbprvf]

Hi, new to RVs, helping my son get his Cypress up and running.
Water heater trips the circuit breaker when unit is switched on.
Obviously a short somewhere in that circuit. Is this a known issue?
WH appears to be a Suburban 10-gal propane unit, pretty damn rusted out.
Happy to replace WH entirely - I'm a builder with 45 yrs experience plumbing/ electric.
What's the best 'modern' way to heat water? Propane definitely preferable.
On-demand? Larger tank? Better modern burners?
Or if this unit is salvageable, how to track down short?
Thanks for any advice!
Rolf in MA

 

[CharlesinGA]

Here is the Suburban water heater service manual. There are 6 and 10 gal models. The rust is minimal, rather common. If you remove the anode rod (it will need replacing) and use a flushing wand to clean out the inside and don't get rust flakes out of the tank, it probably is a good water heater.

Newer version of the service manual with all the cautions and warnings the lawyers added, and color pics.

For an electric short, you will just have to methodically track the wires and attempt to locate it. It could be the element itself.

I have added an annotated copy of your pic to show where the electric junction box, elect element and the anode are located. The anode should be checked once or twice a year.

Pic edited to show location of on/off switch for 120v

Charles

 

[CharlesinGA]

I'm guessing a Cypress is a rather large RV, probably a 5th wheel (10 gal is not common compared to 6 gal water heaters). Is this RV being used for traveling/camping/touring/etc or is it intended to be stationary with permanent hookups?

Charles

 

[Kirk]

Water heater trips the circuit breaker when unit is switched on.

That sounds like you are trying to use the 120V heating element. It needs 12V as well to power the control circuit but it can also operate on propane. I suggest that you download a copy of the service manual above. The second one was published long after the water heater that you have was made so may, or may not be in it, Assuming that the trip is the 120V circuit breaker, that probably means that the electric heating element is shorted and needs to be replaced.

I suspect that what you have is a Cypress fifth wheel, built by Newmar.

 

[rbprvf]

I'm guessing a Cypress is a rather large RV, probably a 5th wheel (10 gal is not common compared to 6 gal water heaters). Is this RV being used for traveling/camping/touring/etc or is it intended to be stationary with permanent hookups?

Charles

Thanks very much, Charles. Yes, it is a Newmar Cypress, large 32-footer, will be stationary while we are building a house, 1-2 years. I didn't realize there was an additional electric element. Thanks again!

 

[rbprvf]

Also, if this unit DOES need replacing (the threads for the anode rod were VERY rusty and corroded), what do folks think about tankless on-demand options like the Fogatti InstaShower line?

 

[CharlesinGA]

Do you intend on installing a large (100 lb or greater) LP tank and connecting it to the RV? The demand units only use gas, and will burn thru alot of it. Most brands do not perform well but the Fogatti has good specs and I have not heard bad things about it (yet) like the others on the market.

That is a 10DE model. It does NOT use 12 v to control the 120v element. It looks like it has a on/off switch just to the left of the heat element, hidden behind the gas valve. That is 120v from the breaker and feeds the heat element adjacent to it. Look at this page of the newer service manual, LH column.

This switch will always be there on a DE model. Some RV manufacturers will add a 120v on/off switch inside the RV in the circuit to save having to run outside and open up the water heater panel to turn it on or off.

Charles

 

[klook]

In a Newmar, I would bet on the interior switch. Also bet on the element being shorted. Use a multimeter and ohm it out. It should be around 10 ohms.

 

[rbprvf]

In a Newmar, I would bet on the interior switch. Also bet on the element being shorted. Use a multimeter and ohm it out. It should be around 10 ohms.

Bet on the interior switch being faulty? In addition to the 120v element being shorted?

 

[klook]

That is a possibility but I meant that the Newmar has the interior switch. The element is shorted out.

 

[Rene T]

Welcome to the forum.
The first thing I would do is check is the 110 volt AC heating element if you have one.
It is very common that new people to the RV world turn on the heating circuit without filling the heater tank and blow the element.

 

[rbprvf]

Welcome to the forum.
The first thing I would do is check is the 110 volt AC heating element if you have one.
It is very common that new people to the RV world turn on the heating circuit without filling the heater tank and blow the element.

That very well may have inadvertently happened, in the year he's owned it. Thanks!

 

[Kirk]

what do folks think about tankless on-demand options like the Fogatti InstaShower line?

Some like them and others do not. They use far more water than the tank type.

 

[klook]

I have installed quite a few and even have one I repaired but I would not put it in my camper. I like being able to use electric when I want.

 

[gwinger]

Very good chance the heating element is shorted. There should be a switch to turn power off to it as the picture shows.

 

[rbprvf]

What is the method for firing up the propane side of a 'Suburban' HWH? We have the valves open, and the HW switch on, but nothing happens when HW is called for...

 

[gwinger]

Need more information. What switch is on? If you have propane/electric there will be at least two switches.
Do you have a panel in the trailer with WH switches on it?

 

[Larry N.]

...the propane side of a 'Suburban' HWH?

Careful of abbreviations- HWH is a company that manufactures slide-outs and leveling systems, among other things- BTW, WH (for water heater) would do better. Not a serious problem, but I thought you should be aware of it.

 

[John From Detroit]

There is also the fact: You don't heat HOT water. (Just call it a WH or Water Heater)

 

[gwinger]

Ye

There is also the fact: You don't heat HOT water. (Just call it a WH or Water Heater)

Yep, technically, it's a cold water heater