Water Heater Leak

[n0mhz]

Hello All:

I have a '06 Marathon XL coach. The water heater has developed a small leak. Looking at the water heater it appears that there are two Atwood heaters stacked one on the other. Would that be that there is a separate water heater for gas and one for electric? Or is it all one unit?

I will need to have the heater replaced but before I find someone locally to do that I want to be "semi" informed.

Thanks in advance.

[Gil_J]

Those heaters are BOTH 120VAC powered. In the world of Marathon, one heats and then the other. Country Coach owners, yours both heat at the same time.

That specific heater is no longer made. The new ones has all of the fittings on the front. There is a replacement that some have successfully used. It's one of the Kuuma models. With the dimensions of yours it should easy to figure out which one. Defender stocks most. https://www.defender.com/search.html?q=water+heater&x=0&y=0

[PrevostNewbie]

What did you end up doing about this? Did you replace the 2 water heaters?

[chiplamb]

The Kuumas are great water heaters, I've put a few in.

[Dthomas9572]

Gil,

Question for you on how my system works, I have a 1998 Featherlight with a Aquahot system. When I purchased the coach the Aquahot would not work so I turned on the breaker that says hot water heater..this worked but I had limited hot water. For the last year the Aqua Hot has worked perfectly and I have left the hot water breaker turned off. When using my Aquahot I can take a long shower with very hot water and after 10 or so minutes it stays very warm forever..

I would love to understand a bit more on how my system works.

Thanks
David Thomas
1998 Featherlight XL

[chiplamb]

The breaker is for the electric element which Aqua Hot tells you is for momentary hot water. For "endless" hot water you need to have the diesel boiler operating. Basically you have a Webasto that heats a large water tank within the AH (big copper coil wrapped around the tank). That's as basic as it gets! Keep the filter changed and use it frequently or you'll need a new nozzle every so often within the Webasto head.

[JCarrollJr]

My CC had the 2 water heaters and it's my understanding that it was for faster recovery since one larger heater has the same element as the smaller (10 gal. vs 20 gal.) so recovery time for the 2 smaller heaters was twice as fast as the one larger one. One of mine sprung a leak and I replaced the two with one 10 gal. heater and haven't known the difference. I think that the two heaters was overkill.

[Gil_J]

David, if you have the power keeping the AquaHot in electric and diesel mode is great option. Your neighbors may like you more too. With both electric and diesel on may reduce diesel burn time when electrically produced hot water is enough. The shortcoming with the older AquaHot was the limited wattage of the electric heat and small size of the hot water reservoir.

[PrevostNewbie]

I too had a small water leak, not too big, i was hoping all the tubing and seal replacement i did would fix this, but there was still some moisture, just the feet that attach the water heaters to the floor were always damp. Today's task was figuring out the water heater system since I was unable to get any hot water, I figured out both elements were bad. One was dead, the second was pulling down my 110 to 90 volts no matter what i did. I pulled out the elements and discovered the gasket that goes between the heater and the tank was leaking. 2 new heater elements, 30 bucks each will be here Tuesday, I will post pictures tomorrow, I had to cut the front panel to get the elements out. There was no way I was removing these from the Bus and disturbing the coolant system at this point. I know they don't make these heaters anymore, I have two of the Atwood EHP-10, the heater element is Atwood #91580.

[PrevostNewbie]

2 new Heater Elements will be here tomorrow, I used a dremel tool with cutoff wheel to cut the front panel. Once I have no more issues I will make a cover for the open area. I am interested to see the new gasket, There was no sign of a gasket when I removed these, just a very thin layer of black material. The bracket sitting in front of the water heater clamps the element in place and holds the tank centered in the sheet metal housing. Fans are drying out the fiberglass insulation.

http://forum.prevostownersgroup.com/attachment.php?attachmentid=16810&stc=1
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[PrevostNewbie]

Yesterday, I had to vacuum the sediment out of both water heater tanks, flush with fresh water for about 15 mins, then vacuum. I did this 4 times for each heater and I think they are pretty clean for 28 years old. The new elements are installed, powered up, and started to heat the water. I only gave them about 15 minutes checking voltages on the heaters, thermostat and cutout, the water didn't have enough time to get hot but it was warmer. I will leave the system pressurized and heaters off overnight to see if there are any leaks before I button it up. I will be glad to put the water system behind me so I can move to the Webasto.

[Gil_J]

Mike, a 30 year old hot water tank that's not leaking or about to leak is pretty impressive.

[PrevostNewbie]

Thanks! maybe it was the silt insulation it had on the inside. It has been sitting at 40 psi for almost 24 hours now and no pressure drop yet.