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Posted: Sun Jun 06, 2010 4:53 pm
by randyp
Michael's post (Ready123) is correct and shows the water heater diagram on page 4 of the pdf. It's the same one as mine. Ya see, the marina installed it and all was well in 2008 and 2009 (I think). But last year I noticed that it took very little pressure from water pump to replenish the spent water in the heater. When I removed the original heating element it had all the evidence of not being submerged in water. I'm going back up tomorrow and will see if only opening the relief valve (as Atwood advised) allow the tank to fill. If this is the case then Atwood's directions in the manual are really lacking. The water heater is tucked away behind my holding tank in what could best descibed as the "engine nook" of the F-26. It requires contortionist moves which my 65 year old fat body is somehow not always capable of. So, no, no pictures of the configuation unless you want me to slip in and be pinned in there for the rest of the summer!!
Posted: Mon Jun 07, 2010 8:13 pm
by randyp
AHHHHH FAHGEDABATTIT!!
The never ending tale of woe about the Atwood 11 gal water heater continues. I got up here, opened the pressure relief valve and turned on the water pump. Nuttin. I spoke with the rep at Atwood and finally just unscrewed the pressure relief valve from the body of the tank. Still nuttin. The water gets to the level of "just over" the heating element and that's it. So, I got a funnel and hose and poured in about 4 gallons of water through the hole where the relief valve was. Here's the crazy thing. Some water started coming out of the heat exchanger nipple right under the relief valve hole. The heat exchanger is a closed loop that runs around the outside of the tank and can heat the water while undeway if you have a FWC system or are driving and RV. Since I have neither this has never been hooked up.
Anyhoo.....after the water drained from the nipple I reinstalled the relief valve and hooked up all the plumbing (there is NO restriction of water flow in and out of the tank or at the hot water taps in galley and/or head sinks). I turned on the electricity and the tank seems to be heating (the pressure relief valve is hot and it sort of acts like a big heat sink since it's brass.
After 3 hours I got a "little" hot (warm actually) water out of the tap and then it goes back to cold again.
WAAAA WAAAA. Looks like I gotta take my baths in the lake and throw all the dirty dishes into the lake too.......
Posted: Mon Jun 07, 2010 9:04 pm
by Big D
Randy, I think the port right under the relief valve is cold water "in", not the heat exchanger! The exchanger fittings are stainless pipes with a nipple on each end. The fresh water "in" and "out" are fittings (hopefully brass, maybe plastic) that are screwed (threaded) into the tank.
Again, I think it's hooked up wrong. It just keeps getting stranger! If you pour water into the relief valve hole and you are getting water out of an unused hole, then you are using the wrong holes unless your exchanger is punctured and if it were, you would have been getting water pouring out of there whenever you presurize the system.
Don't give up. I think a few of us are scratching our heads, so we want to find out what's going on.
Posted: Mon Jun 07, 2010 9:46 pm
by Big D
Randy, hope this helps.
- "B" is cold water "IN" which is just below relief valve. Water would come out of here if you poured water into the relief valve.
- "A" is hot water "OUT"
The tubes (stainless) sticking out of the tank are the exchanger hook ups for the engine.
Where are your potable water hoses hooked up to?

Posted: Mon Jun 07, 2010 10:19 pm
by ready123
randyp wrote:I got up here, opened the pressure relief valve and turned on the water pump. Nuttin. I spoke with the rep at Atwood and finally just unscrewed the pressure relief valve from the body of the tank. Still nuttin. The water gets to the level of "just over" the heating element and that's it. So, I got a funnel and hose and poured in about 4 gallons of water through the hole where the relief valve was. Here's the crazy thing. Some water started coming out of the heat exchanger nipple right under the relief valve hole.
NO that is the cold water in as shown on my pdf link and BigD's copy of it.
The threaded fittings are where the water goes in and out.... it sounds like you have the hoses clamped to the heat exchanger stub nipples.
You need a threaded fitting to connect your water to the tank.... is that what you have or have you just clamped your hoses to the stub nipples which are for the heat exchanger to be fed by hot engine water????
Posted: Mon Jun 07, 2010 10:40 pm
by captainmaniac
Just to reinforce what Ready and Big D are telling you -- look at the PDF.
Page 1, Installation section, point 3 ... "Connect both 1/2˝ NPT water lines (FIG 1-A hot water outlet female and FIG 1-B cold water inlet female)"... this is A and B on the diagram Big D reposted - which is right out of the manual. Look at diagram 3 in the manual. Clearly shows that he engine plumbing goes to the lower ports that have the nipples.... Simply put - it's not plumbed right.
Posted: Tue Jun 08, 2010 10:22 am
by randyp
THANK YOU! I am renouncing my US citizenship and becoming a Canadian! But then again, you probably don't allow dummies in.
You guys finally hit up the side of the head. Replumped correctly and the tank filled. Now to see if I cooked the heating element. I have continuity when I put the meter on it, but I do have an extra. When the marina recommissioned the BH this spring (or when it was laid up and winterized in the fall) they must have hooked up the hoses to the heat exchanger fittings. It would be an easy mistake since the cover is stamped "C" and "H" closest to these fitting not the brass ones. Not being all that familiar with the water heater I just figured it was plumbed correctly.
Ay yay yay!!
Thanks again.
Posted: Tue Jun 08, 2010 2:03 pm
by Danny Bailey
No need to leave. It was an American who first told you it were'nt plumbed right....look at the second reply you got. Ugly is only skin deep but stupid goes all the way to the bone.
Posted: Tue Jun 08, 2010 2:32 pm
by randyp
OK. I'll go for dual citizenship, although right about now I'm feeling so stupid I doubt either country wants me. Thanks for the earlier advice that I obviously ignored. Sometimes I have to be snakebit before I wake up.
Posted: Tue Jun 08, 2010 2:46 pm
by Danny Bailey
Mistakes are great if you learn something from them....not so good if the same ones are made over and over.