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Old 05-06-2017, 06:34 AM   #1
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Location: Ohio
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No Hot Water Flow

Its evening the campfire is winding down we decide to head into the camper for the night and get ready for bed. Our routine starts out normal, come inside turn on the water heater to warm up for showers and read while we wait. The allotted time has passed, water should be ready, go and turn on the shower and no hot water. When I say no hot water I should clarify more, no hot water flow, it is just dribbling out. This is how I found the problem, my temp fix and permanent solution.

I accessed the back of the water heater and I can feel the hot water outlet pipe is hot for a few inches and then is cold. After phoning a friend (JohnB) for some possible insight, we narrow it down to something wrong with the water heater bypass check valve, thinking it may be stuck. This is the brass fitting on the top of the back side of the water heater. I turned off the water pump and heater and shut off the circuit breaker for the hot water heater and go outside and drain it.

Once it was drained I went back inside and unscrewed the right angle plastic fitting on the back of the bypass valve to see what I could find. Not having one apart and knowing how it worked, I saw the plastic disc and o-ring, I poked it with a screw driver and it wiggled around. Seemed to be not be stuck now so I screwed the fitting back on, turned the water pump on to refill the water heater. Once refilled I checked and still no flow. I gave up for the night and planned a trip to Home Depot in the morning, to buy a short brass pipe to eliminate the bypass valve, so we could have hot water again. This temp fix worked without a problem, but now have actually taken it apart and seen how it works I could have fixed it that night and showered away.

The bypass valve is a brass tube with a plastic barbell looking piece in the middle. This barbell is a two piece item with one end molded and the other end snaps on once in the brass fitting. When you switch the plastic valve at the bottom of the water heater to bypass it the water pressure pushes the o-ring end back into the brass fitting to seal the water from going backward into the top of the water heater. The end that snaps on is on the inside of the water heater, what happened is that it fell off causeing the normal flow of hot water to push it all the way out of the brass fitting and stop when it hit the right angle plastic fitting. This then blocked the flow of hot water. When I drained the water is fell back down into it normal position so when I looked at it I didnít think anything was wrong. Now knowing this I could have just pulled the half of the plastic barbell out and then the bypass would just be an open brass fitting I could have showered when I refilled the tank, no trip to the store required.

You can see the snap on end is a little worn, the snap on piece is somewhere in my water heater now I guess.

Since my temp fix was eliminating the brass bypass fitting when the end of the camping season rolled around I would need to replace the valve so I could winterize the camper. I decided that I didnít really want to have this happen again and decided to install a manual valve instead. If I was going to switch one valve to bypass why not two? This solution was easy I just replaced the top tee fitting with a 3 way Pex valve like the bottom has since I already had the brass fitting replaced.

It was about $10 (at the time) on Amazon, just unscrewed the old tee and screwed the new tee valve in. Note that this is directional and to check which way before installing. This solution should work on any camper with a similar hot water heater setup, which is probably most.


Current Camper: 2006 Sunline T-264SR
Previous Camper: 1998 Coleman Mesa
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Old 05-06-2017, 06:30 PM   #2
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Hi Ben,

Great post!!! This check valve failure is somewhat of a camper classic text book failure. It happens every now and then and our forum has had this before. But we never had any pics that I can recall. Now we do!!!

Seeing those parts, I "think" I might know what your missing valve stem keeper looks like that is rattling around in your hot water heater. There is most likely a spring too.

See this post of mine on the fresh water inlet check valve. Those of us who push that little plunger with pressure on the system will "normally" only do that once as the check valve then leaks like a sieve...

This fresh water inlet check looks like it is made just like your hot water check. B & B and Marshal Brass use to make these. B & B may still.



Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
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Old 05-08-2017, 06:46 AM   #3
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You guys make a good team! Thinking on your feet is what true campers do best. Congrats. Good job!

Terry & Marsha/Northeast Illinois
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Old 05-10-2017, 08:33 AM   #4
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Looks great Ben! Crazy how one little thing can basically shut down your water heater.
2007 T-286SR Cherry/Granola, #6236, original owner, current mileage: 9473.8 (as of 6/18/21)
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Old 05-18-2017, 06:28 PM   #5
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Good troubleshooting and fixing BenB. We are about to take home this 2000 Solaris and the current owner mentioned about the water heater acting up. Will take a look at it right after we finished installing the Smittybilt stuff on the current jeep project. Excited to work on this thing and hit the road.
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