Water Heater Replacement Info

[jmowrey]

Here is some info about issues with high altitude operation of water heaters which might be useful to others:

Our new-to-us Dolphin has a water heater in it that looks pre-Civil War. The bolt for the anode rod is so rusted I wouldn't even venture to try remove it for fear of damaging the ancient tank. So we are replacing the water heater before it springs a leak. Unfortunately, the 12 and 3/4 by 12 and 3/4 opening won't accommodate an Atwood water heater, which would have been our first choice. So we are having a Suburban SW6D put in (propane only w/electronic ignition inside the cab).

On reading the manual which I was able to download, I ran across a section about high altitude deration. They suggest replacing the burner orifice with a high altitude version if the unit will be used at over 4500 feet. We were a little concerned about this because we are in Santa Fe at 7000 feet and plan to use our Dolphin for the next few years (until we can retire and take longer trips) just in the Northern New Mexico area. The part that seemed strange to us was that they recommend you go back to the stock orifice when you are below 4500 feet. It was hard for us to imagine, being new to RVing, that people actually go have their orifice replaced every time they change altitudes.

After talking to a tech guy at Atwood (who seemed very uninformed and very disinterested) we discovered there is a similar issue with Atwood water heaters. The advantage of an Atwood heater though is that they have a collar on the burner tube which allows for adjustment of the air intake to help compensate for the thinner air at high altitudes. Apparently, Suburban quit using an air adjustment sleeve back in 95. So there is no easy way to compensate for the richer fuel mixture at altitude. The guys installing our water heater had never heard of this issue (kinda scary). But they say they have installed and repaired lots of Suburban water heaters and never had a problem or a complaint about high altitude operation. They came to us highly recommended, so we're taking them at their word.

I talked to a tech guy at Suburban and he was very helpful and seemed very knowledgable. Granted, he works for Suburban, so he has that bias, but he told me we likely won't have any problems unless we go well over 8000 feet. Most of their tech calls about this issue come from Colorado. They put the 4500 ceiling in the manual to cover their butts. He said a lot of installers don't know about this issue because it isn't an issue for very many people. He figured it was a good sign that the guys doing our install here in Santa Fe hadn't heard of the burner tube replacement. It means they haven't needed to do it for anyone. (Of course, it also means they have never bothered to read the manual. Again, kinda scary) If we do have problems, he said changing out the burner orifice tube is an easy, ten minute fix I could do myself. Judging from the parts catalog illustration, he is probably right. The tube is right in front and there is one nut and a copper fitting to unscrew.

So we are going to assume the Suburban tech guy was giving us the straight scoop. We're going to go ahead with the Suburban water heater and I'm ordering the high-altitude burner tube ($25) to have on hand, just in case.

It will be nice having the electronic ignition switch in the cab instead of having to go out and hand light the water heater every time we want to use it. We should be able to conserve on propane, too, by being able to turn off the water heater when it's not in use and re-light it only when we need it. If it's like our current heater, it only takes about 20 minutes for the water to get hot enough to wash dishes, etc. I've been too lazy to do that as often as I might have when it was necessary to go outside to turn it off and on and to light it. There have been a couple of occasions when it was actually too windy for me to be able to light it manually.

We will be picking up the Dolphin from the mechanic on Thursday, then taking a short trip to about 7500 feet this weekend. I'll post again if I have any troubles with the new water heater.

Joe

[sdboltdude]

I just installed my suburban 6al with the switch and yes the switch is a great upgrade..

plus it has a 3 heat setting you can use tell your installer to show you switch..