Low hot water flow on 2016 Itasca Sunova 35G

[spydorman]

We are camping with electric only running water off our fresh water tank. We have an Atwood GCH10A-4E Hot water tank. Cold water runs fine, but hot water from all faucets is a trickle. Water is heating up though. I turned the WH bypass valve and all faucets run fine, so problem is before the bypass.
I suspect either a large calcium buildup or the check valves are bad.
Was wondering if anyone with a coach similar to the 35G has tried to gain access to the rear of the tank to get to the check valves and if it's even possible to get to them there without removing the tank. Also if possible, I was thinking of replacing the heating element or should I follow the ain't broke don't fix it rule?
One other question. Is it best to drain the WH tank and leave it empty after each trip or just leave the water in it? I've been doing the latter.
Thanks! Carl

[be happy]

You might try looking here for how the lines run
https://www.winnebago.com/Files/File...m/Plumbing.htm

I used to have a coach that had somewhat the same problem. When putting the slide out (drivers side) it would cause a kink in the line going to the water heater. I found that by putting water pressure in the lines before moving the slide out solved the problem. Once i figured that out I was able to find the location of the water line causing the problem and was able to fix it. I do not know if this is your problem or not but sure sounds like it.

I would not change the heating element, it has nothing to do with the flow of water.

As for leaving water in the tank or not. Once I fill the tank after de winterizing it stays full until winterizing. The only time I drain is if I go somewhere and get a bad water smell.

[spydorman]

Thanks for the come back. I don't think that my problem would be caused by what you describe. The water heater bypass valve is located near to the WH. If I set it to bypass the tank the water flows fine out of the faucets. When I turn it to go thru the WH the flow decreases again, so I think that my restriction is occurring in the Water Heater.

[Morich]

A spot which has all kinds of good ways to look at lots of the parts on an interactive site is here for your specific RV:
https://catalog3d.winnebagoind.com/2015/15ifd35g.htm

This does not give much info on how/ where to get to those parts but it may help to know they are there?
It shows you have two types of check valves with one on each line, in/out!

Click these snips to get a better view or go direct to the parts drawing?

This will also let you find an item in the PDF style list at right if you know the name and when you click it there, it will light that item in yellow to help spot it on the drawings.
Works the same in reverse if you click item on drawings, it highlights that on the parts list.
One way to get the "real" name of parts I find that I don't know!

The question of drain or not may depend on how you use the RV.
We do not go often but the RV may set for several weeks between trips, leaving any water with the remaining bacteria to get warm and let that bacteria multiply hundreds of times.
So how we use that water can also matter. If we use the water for cooking rinsing food, etc. after it sets for several weeks, there is a good chance we are raising our chances for illness from the polluted water.
Things like rinsing pasta come to mind!

We just feel it worth the time to open the drain and get away from any questions of being safe to use it any way we need. But I also add a small valve to open rather than pulling the big awkward plugs as I do for winter.

Point to keep in mind is the level of water treament is set to cover the normal bacteria public water, not enough to kill ALL bacteria but just enough to get it down to safe to drink for most people.
Even bottled water has expiration dates due to the bacteria growing over time, even in the closed bottles.

[Mark w]

One is behind water heater had to remove water heater to access. Other is behind water valve control panel. Both have failed at different times Replaced with solid brass checks. Water heater removal not too bad did both at a campground 2 different places. Good luck

[spydorman]

So, kind of figured it was the check valve. Found a YouTube video online about changing it here:

https://www.youtube.com/watch?v=wpXS2OAUjn8

Took the access panel off of the back of the WH compartment. Held on with two screws and a little caulk on both sides. Came off pretty easily. Both check valves are in this compartment. Had a couple of magnetic lights my wife bought me for night time barbecuing and used them to light up the area. With the cover off you can get to the top outlet hot side check valve pretty easily. From what I read this is the one that usually fails. Removed the plastic nut from the valve after draining all the water out and making sure the heater was turned off. Couldn't fit a socket wrench in there, so had to use a 1" open end combination wrench. Mine broke loose pretty easily. Got it out and sure enough the poppet was loose inside the valve and the spring and retainer weren't present. From the video I watched he showed the spring down inside the fitting on the tank. Its pretty tight with the suspension and frame close by, so had to use a mirror to look into the hole. I could see the spring and the retainer in there, but it was a lot deeper in than what was shown in the video. I tried a bent wire and an awl, but trying to hold the mirror, manipulate the wire and get it to catch the spring way down in there just wasn't working. Reverse image from the mirror wasn't helping any either. Thought about flushing them out with water, but didn't want to fill up the cabinet with water. Then thought of using my Shop Vac to try and suck it out. Removed the drain plug and opened the relief valve so air could get into the tank, applied the vac and it sucked both pieces out really quick. Wish I had thought of it sooner.
When installing the new check valve the line with the plastic nut on it is hard to bend to line up with the outlet of the check valve. Not wanting to strip the plastic threads, I threaded it on the check valve before threading the check valve into the boss on the tank. You need to tighten by hand the plastic nut every few turns of tightening the check valve to keep it on, but it really helped get things assembled easier.
While I have everything open, I am going to do the Vinegar cleaning process of the tank to remove any calcium deposits.
Thanks for the suggestions. Hope this helps someone.
Carl

220622-Chk Valve.pdf
220622-Back of HWT.pdf