When to replace the water heater? (original 2004 unit)

[lbdesign]

I have a 2004 AS with an Atwood 6-gallon electronic ignition gas water heater.
There's a problem with it, and my primary question is: to repair or replace? It's 9 or 10 years old, and sees frequent use. How long do the water heaters last, and should I just order a new one and have it installed, rather than go through the repair dance of waiting for parts and trying different things?

The problem is that it's not lighting. I see the sparks from the ignition device, but the propane does not flow. I have good propane supply, and the stove and hot-air furnace work, and I smell no leaks, nor am I losing my propane from the tank.

And if the consensus is to replace, what what should I replace it with? I see many discussions about different brands, plus dual electric/propane, and tank vs tankless (continuous) models. It's a lot to consider while I take my sponge bath ;-)

thanks in advance!

[mandolindave]

It still worked when I replaced it. My restoration guy told me at 30 years I was running the risk of having a big leak in the midst of a nice outing.

It might just be spiders or mud daubers, and need cleaning. So try cleaning the gas supply tube and nozzle. The boards on the new auto igniting units do go bad sometimes.The board is very easy to replace but cost about $200. Sometimes the thermo sensor goes bad. They aren't expensive. OR.....the thermo sensor may need adjustment. A new water heater is about $500 but installation would be a few hundred more. I have replaced a few for friends and it wasn't that much fun.

[Aage]

Before you give up on it, get an aerosol can of compressed air, and blow it into the big air tube where the flame blows into the heater. Heater off, of course. Ours regularly gets plugged up with spiderwebs, and will not burn consistently until I do that.

Don't stand in front of where the exhaust from that tube comes out, you will get a dose of spiderweb soot!

Failing that, replace the thermocouple and pilot light; they are user-replaceable parts that are key to having the heater work properly.

[Condoluminum]

Even if self repair doesn't work, cost to take to a shop for repair is going to be cheaper than replacing with new.. Useful life of 15 to 20 years is more common, and best reason to replace is either completely corroded burner assembly or leak in tank and primary water pipes in and out of tank.. Since you have neither, just replacing gas burner valve or ignition system ought to be least expensive option, and keep going a while longer.. (Ours is 25 years old, has had new thermostats and thermocouples, and a service/cleaning, but still works well..)

[mandolindave]

I don't think that the large combustion tube is much of an issue. I think that you are actually cleaning the nozzle and the smaller supply tube as you are cleaning the larger combustion tube.

[AirsDream]

They are prone to lots of things that can make them not work right, as noted above. Spiders and mud daubers can plug the gas orifice or make it weak or misdirected, and the circuit board that controls the gas solenoid valve or the valve itself can fail.

But are you sure you're getting no gas? On mine, especially after it's been in storage for a while, it takes a long time for the gas to get all the way to the rear of the coach to the water heater. So I do this: a.) turn on all the stove burners and work the igniter until they all light; b.) turn on the furnace and run it until it ignites; c.) turn on the refrigerator and run it until it's on; and THEN, with most of the line bled by running these other appliances, I turn on the water heater until it lights. The first time each season, it might take ten or more attempts before it lights. Thereafter, it pretty much lights every time. But after each long period of non-use, I have to go through this longish bleeding procedure before it will work. [I thought I had a gas leak, but can't find one - I now think it's just the nature of the beast.]

Also, at least on mine, the circuit board on the water heater has a "proof of flame" sensor that it relies upon: when you turn the heater on, if it does not get feedback from the igniter / thermocouple within a few seconds that there is a reliable, hot flame, then it shuts down the gas solenoid valve and sets an error light on the on-off switch. This is a safety feature that's designed to prevent the gas from just running and running when there's no flame to burn it ... which would present a potential fire and explosion hazard. So when you turn it on, if it doesn't light, the gas solenoid will only stay open for a very few seconds ... the consequence of this is that it can take a bunch of attempts before the line gets bled of any non-combustible air/gas mixture and the good stuff gets to the burner. So if you're certain that there isn't e.g. a mud plug in the way, etc., then do try cycling the heater on, wait for the error light, and try again several times in a row.

Good luck.

[dznf0g]

Mine lasted 22 years in the pop up which I bought from Mom and Dad. Still worked when I sold it. In My next SOB it lasted 17 years and worked when I sold it. It is usually the controls and gas supply components which need work, but the tanks are pretty robust. With a 2004, I'd probably fix if the repair cost was less than half the replace cost.

[mandolindave]

When a water heater is new or working great because it is clean, it will make a LOT more noise, than a heater that is clogged up with spider webs. ( I have been told that spiders LIKE the smell of propane. I don't know who asked the spiders, or even more of a wonder, who understands whatever language that spiders speak).

[Aage]

Originally Posted by mandolindave

I don't think that the large combustion tube is much of an issue. I think that you are actually cleaning the nozzle and the smaller supply tube as you are cleaning the larger combustion tube.

Maybe I would be cleaning the nozzle and smaller supply tube if I was pointing at them, but; I point the airflow in the same direction as those two items point.

That and the small cloud of gray soot tell me that the combustion pipe IS the issue.

Not saying those small bits don't get dirty, but the first time I tried blowing out the combustion tube was after having replaced the small bits to no avail. Blew out the big tube, blammo, it lit like a trooper.

I now do it once a season, and it comes back like new each time.

[lbdesign]

Thanks everybody! Some clarification: It's been in constant use, because for fun, I'm wintering in it, so it's not a storage unit, and the propane supply is flowing freely elsewhere in the Airstream. It worked one day, and then the next it would not light. I will try the canned air approach, but doubt that in an in-use heater the insects would have had a chance to block it. But you never know -- they are industrious. Visual inspection shows no obvious problems (wires intact, etc).
It sounds like fixing is more prudent for now, and hopefully it will be something we can fix on the first attempt. Though I was warming up to the idea of getting a gas/electric replacement for the flexibility.

[Larry C]

A friend of mine with a 2005 AS just had the same problem you describe. We changed the gas solenoid valve, that solved the problem, and took about an hour, including going to buy the part..
Good luck!

[n2916s]

Replacing the gas solenoid is a lot cheaper than a new unit. Mine failed after about three years, replaced and it has worked happily for about four years now.

Mike

[BeachHouse]

In my 2005 trailer, mine stopped working a few weeks ago. After testing various things myself, I took it to a RV service place and they messed with it. Eventually they found it was just an inline fuze for the overheat t'stat. It isn't a regular fuze, I think it was $10.

[lbdesign]

I've waited to post because it's not fully fixed yet, but the problem here appears to be an aged gas solenoid valve. Cleaning it helped but was not enough. It stopped working again after 2 days. I'm getting a new solenoid valve installed tomorrow. (The part costs about $150)

[lbdesign]

Also, my repair guy says everyone should have an anode rod, even though I've read somewhere here that Atwood claims their design eliminates the need for it.

[lbdesign]

Picture of the inline fuse JupitorJ mentioned, and the solenoid valve:

[vswingfield]

Water Heater Repair Decision Tree:

Is It Leaking?

Yes
Replace

No
Repair

That's pretty much it. I will admit that there will be some exceptions, but as long as it's not leaking repairing it will be both less expensive and less work.