Hot water heater problem

[scroon]

After spring startup I'm only getting warm water from the fixtures the bypass valve is open. I can hear the water heater kick on but I'm getting only warm water. I have 2017 25 foot rear bedroom queen any suggestions I don't know where the mixing valve is located or what it looks like to tap on it.

[CRH]

Shouldn't the bypass be closed?

[OTRA15]

Originally Posted by scroon

After spring startup I'm only getting warm water from the fixtures the bypass valve is open. I can hear the water heater kick on but I'm getting only warm water. I have 2017 25 foot rear bedroom queen any suggestions I don't know where the mixing valve is located or what it looks like to tap on it.

Was your AS winterized? If so, the technician/mechanic is the most direct feedback IMO. I would look under the bed, the bypass valve is attached to the water heater. Find the heater inside one of your exterior mechanical space doors, and work backwards from there to locate the valve.

Check your owner's manual for the location and function of your mixing valve.

Guessing your mixing valve is open, allowing the cold water supply to the water heater to mix with the hot water coming out of the heater.

See diagram in last post.

Good luck,

Peter

[scroon]

The hot water heater is not bypassed I turned the valve to fill the water heater. The water is starting to get hotter but not scalding hot I'm thinking there is still air in the lines.

[OTRA15]

Originally Posted by scroon

The hot water heater is not bypassed I turned the valve to fill the water heater. The water is starting to get hotter but not scalding hot I'm thinking there is still air in the lines.

In your Airstream, can you see the three valves shown in Post #2?



. . . and what is the position of the three valves? The upper and lower valves should be open [handles over and parallel to the pipe], and the middle valve should be closed [perpendicular to the pipe]. Do your valves look like the top part of this image? If the middle valve is open, close it and see what happens.

Earlier you said in Post #1:

Originally Posted by scroon

. . .
. . . I don't know where the mixing valve is located or what it looks like to tap on it.

Are you now able to see your valves?

Thanks,

Peter

PS -- If you have opened all your hot/cold sink, shower, and toilet faucets etc. [and water ran out with no air], there is no air left in your lines.

[Adventure.AS]

Originally Posted by OTRA15

In your Airstream, can you see the three valves shown in Post #2?



. . . and what is the position of the three valves? The upper and lower valves should be open [handles over and parallel to the pipe], and the middle valve should be closed [perpendicular to the pipe]. Do your valves look like the top part of this image? If he middle valve is open, close it and see what happens.

Earlier you said in Post #1:


Are you now able to see your valves?

Thanks,

Peter


PS -- If you have opened all your sink, shower, and toilet faucets etc., there is no air in your lines.

The 2017 AS doesn’t have the three valve bypass arrangement like earlier years. There is only one valve to turn to move it from bypass to use mode.

They can be damaged with too high air pressure when winterizing. The mixing valve doesn’t have a stellar reputation for longevity and may need to be replaced. Some technicians recommend removing the mixing valve and reverting to the three valve system. If this is done the thermostat in the water heater should be replaced with a lower temperature version. You will also reduce the volume usable hot water (6 gallons vs virtual 9 gallons).

[OTRA15]

Thanks Ray, good points.

scroon, sorry for the mix-up. Good luck in the O. R. [see next post ]

Peter

[scroon]

I don't have the three valve system just the one bypass valve I hope I don't need a bypass surgery [emoji6]

[wulfraat]

Correct the 2017 only has a single valve for the hot water heater feed, no more 3 valve bypass like my 2008 had.

Having the same issue with my 2017 ‘30. De-winterized today. Spurt of very hot water then just warm / cold flows with reduced pressure as compared to the cold line.

Traced issue back to the Atwood mixing valve ar the rear of the hot water heater.

Pain in the but need to get a new mixing valve, remove the dinette bench and some other trim, replace and put it all back together.

I’m under warranty so hoping airstream can just send me a new valve and I’ll do the work myself rather than waiting in line 3 months at the dealer only for them to mess something up.

New mixing valve is about $125 bucks if you are not under warranty. Here is a picture of the failed mixing valve.

[scroon]

Ok I'll will try that

[Malia20]

Check your outside shower. I have not experienced this but was warned during my dealer walk-through...If the outside shower hot & cold valves are open and the water turned off at the shower head (in which case little or no water is flowing), you will only get warm water anywhere else in the trailer. Something about the hot & cold valves being open allows the hot and cold water to mix producing only warm. It's a quick fix if that is the problem.
Good luck.

[wulfraat]

Originally Posted by Malia20

Check your outside shower. I have not experienced this but was warned during my dealer walk-through...If the outside shower hot & cold valves are open and the water turned off at the shower head (in which case little or no water is flowing), you will only get warm water anywhere else in the trailer. Something about the hot & cold valves being open allows the hot and cold water to mix producing only warm. It's a quick fix if that is the problem.
Good luck.

Correct, part of the troubleshooting process. My outside shower faucets were closed but good call out.

[scroon]

Will do thanks guys

[abqdor]

I've searched most of the threads regarding the Atwood hot water heater. My '16 Flying Cloud has developed a hot water problem which sounds like the mixing valve. Hot water seems to be more available when turned to the cold side. Is this possible? When we turn any of the faucets to the hot side, it is just a trickle. The only way we can get more pressure and some hotter water is to turn the faucets toward the cold side.

I winterize using an air compressor and have read that this can cause problems, but I close the single bypass before winterizing, so I don't understand how that affects the mixing valve.

Some people have replaced their mixing valve and others have regretted replacement because they were able to clean the screens of the problem valve. I'm looking for suggestions as to how to proceed.

[Daquenzer]

Sounds like you have a mixing valve problem. There is a valve on the top of the hot water heater that makes sure the water going to the faucets are not too hot and mixes it with cold. If it isn’t working right it will shut off hot water. There is a temperature sensor on the valve (black part). This can get corrosion etc. on it. 1. I had this problem. I took the valve off and soaked it in white vinegar as suggested by a technician. It worked. I got hotter water, but not real hot. 2. I did replace the valve with a new one. Works great now. Valve costs about $120. I kept the old valve and soaked it longer. This is a common problem, so you may want a back up valve.

[abqdor]

So I took the leap and removed the mixing valve. I found only one screen in the three ports and it was clean as shown in the photo.

I pulled the port apart, just to make sure that both sides of the screen was clear. Before removing the C-clip, I noticed that one of the parts was not properly seated. It was stuck at an angle. There is a small spring between the "stopper" (for lack of a better word) and the top ring. Once I got everything apart, it was obvious that the stopper was supposed to slip into the center of the top ring in order to move up and down freely, so I put it all back together with the stopper slipping into the center of the top ring.

I have the whole assembly soaking in vinegar, just to make sure before putting it back in, but was wondering if anyone else has had this type of problem. I'm not sure what would have caused the stopper to unseat in the first place.

[abqdor]

Put the mixing valve back in and hot water is back to normal. On my Atwood 6 gallon heater, the only screen is in the port coming out of the hot water heater. It apparently was the stopper that was jammed sideways and not sediment causing the blockage.

Not sure what the function of the stopper is or how it got sideways, but it appears to close in the direction of the heater tank and must prevent water from going back into the tank.

The only pain to the whole project was removing all of the plywood under the twin bed in order to access the valve.

[jcwall]

I sure could use some help. My hot water heater is working fine. I have the higher temperature T-Stat. Water in the tank about 150°. No hot water the shower. Luke warm water to gallery and bathroom. I put in a new mixing valve. No change. Finally I bypassed the mixing valve entirely. Hot water goes directly into a pipe which runs directly to the bathroom faucet. It does not come out anywhere near 150°. At an RV service center right now and the tech is stumped. Dealt with a veteran tech at Dometic and he was stumped. i’m stumped. Anyone have any ideas?