Ouch, no HOT water???? 2002 Itasca Horizon 32TD

[dawgout]

Help!
I have a Itasca 32 TD MH 2002.

It has an Atwood GCH10A-3E hot water heater. I am at wits end with no hot water.

It runs hot for about 20 seconds, then goes cold.

Here is what I have tried, and tried and tried......

1. Check and clean all connections including putting in the two new thermostats. Also checked the 3 amp fuse and everything checks out.

2 Changed the outlet check valve on the hot water heater.......ouch that is hard to get to, but finally got it.

3. Both indoor and outdoor shower valves are closed to prevent crossover. Checked numerous times.

4. If I shut the bypass valve, I get NO hot water flow to any hot water outlet inside or out in the coach. If I leave it open, I get the 20 seconds of hot water then cold, but at least get full water pressure. I strongly suspect I am missing something in this area, but I have talked to numerous people and can't figure this out.

If anyone has other ideas to try, I would greatly appreciate it as my wife would love a hot shower.

The water in the tank is hot, just never makes it to the faucet.

Thanks for your input!

[Morich]

I might throw some ideas in to let you think it over?
How familiar with RV water heaters are you? Are you used to hearing them light and heat the water for a bit before shutting the fire off?
Does the fire come back on as you try to use hot water?
What I'm getting at is the idea that the thermostat may not be letting the water get hot enough or if new to the game, possibly not waiting long enough?

Also it may be helpful to know how the hot water changes to cold. Somewhat slowly like the heater is just not keeping up with the use or is it hot and then suddenly cold?
If the hot water is not hot enough and it is only 6-10 gallons, we may use it all up and then it becomes colder as there is a smaller amount mixed with the hot we get at the faucet.
If you turn on a faucet with only hot water, does it start hot and then gradully get cold?
Not getting hot enough, might be due to a bad thermostat. They are often just a small "button" type thermostat on the side of the tank. You might see it sticking out with a couple wires attached?

But there is also a funky, tricky item that can fail in ways to fool us. Do you have a bypass knob like this drawing?


This is often a plastic setup and the shaft inside which makes the actual change in flow can seperate from the knob in weird ways!
It can work well to toally close flow but then it can sometimes not open fully to let the water though to the heater and on to faucets. This can make you start with full hot water in th eline if you've waited but tthen when that water is used to get as mix of large amount of cold with just a bit of hot, making you think it is ALL COLD?

Or is it possible there has been a different bypass setup added over the years? Somebody possibly added an after market type and there are two knobs which need to be set right and you may only be setting one?

Sorry, more questions than answers but maybe we can get the discussion started!!


See if any of that makes sense

[dawgout]

Thanks!

I have 3 inline valves.....one on hot out, one on cold in and then the bypass. They are straight forward with parallel to line "ON" and perpendicular "OFF"

If I turn shut the bypass one, the water quits flowing altogether in the coach.

If I leave it (bypass) open, I get 10-20 seconds of hot water, then goes cold quickly and cold water faucets all run fine.

I just replaced the thermostats and checked the fuses. The heater fires up and keeps running until tank is hot (can test two ways by turning on hot in coach and getting 10 seconds of HOT and by releasing pop off valve on top of tank....HOT).

I also replaced the "out" check valve on tank. Although when I got the old one out, I was disappointed because the spring valve was already missing, so I am guessing a PO had been there some time before me and simply tapped it out when it stuck before....just a guess.

Tomorrow, I will post a picture of my valve set up. It looks legit and was working for the two years previously I've owned it.

I'm still puzzled.
Thanks for your help!

[Ray,IN]

Your last explanation sounds like the water heater inlet check-valve is stuck shut. Winnebago installs a check-valve on both the cold water inlet and hot water outlet. If either sticks closed you have no hot water.

[dawgout]

Ray, that makes sense and I did not know that. I will check that out today. Thanks much as I was at ends to even know what to try.
Thanks
Doug

[Morich]

Question on that idea? If the inlet valve is stuck shut, would you get any water into the heater to be heated? You do get "some" hot water, so doesn't that rule out a stuck inlet check valve to not let water into the heater?

I'm thinking this is an after market bypass a PO has added and that may mean it has lots more questions. Is it actually installed right to bypass the heater? Maybe yes, maybe no!

So I would have to look carefully at the way it is installed before going too far.
So I would go this way:
1. find the valve that lets water go into the tank. We know it works when turned right as you do get hot water! Like you've mentioned, if you flip the pressure relaif valve just a bit and water comes out, that valve is right!
2. Find the valve on the line going from the tank out to the RV and open it. Test to make sure you do get hot water to the faucet, even if one for a bit. It may not last long but that is where a third valve may be set wrong.
3. Find that third valve which forms a path between the in put and output of the tank. close that one to stop that route.

I feel what may be happening is that you are ony getting one of the two valves set right. Can't prove it and might be wrong but I think what is happening is that you get some hot water but the last valve being open means you get a mix of hot from the heater mixed with a whole bunch of cold directly bypassing the heater.

Aftermarket bypass I've used takes changing two valves to bypass for winter or reset for use!

This is not the way the bypass actually works and I've forgotten where the third valve fits in but the idea is that we want to keep the pink from going into the heater so we close a valve in the input line and set it to allow pink to flow past the heater to the hot water lines. But we also have to close the path back to the heater to avoid filling it with pink.
So I think there needs to be TWO valves changed at any time we want to switch from normal use to bypass or from bypass to normal!
I'm thinking only one or two valves are right right, rather than all three. try to think like a drop of water and follow the route looking for how to set the valves to get only hot water without a cross connection to to allow for getting a "mix" of hot and cold when set to normal.

Hint?
I had to write it down, so I didn't have to think so hard every season!!

[dawgout]

My troubles turned out to be a cold water check valve on the hot water tank. Ray, you finally helped to solve what has been a very perplexing issue for me.

I did not realize there was one on each of the inlet and outlet sides of the tank.

Both are now done and finally it turned out to be the cold water valve.

On this coach, the valves are tough to get to, but FINALLY got it done.

THANKS to all who helped troubleshoot this and spent your time helping me.

Very appreciated!
Doug

[Wneels]

Look for nest in air intake or exhaust pipe. Tripping high temp safety switch