Hot Water Tank no flow.

[Flintstones Adventurer]

This past week-end my hot water tank was determined to get my attention, and so it did.

Upon arriving at the campsite, and hooking up the water hose, everything seemed fine. Good flow in both hot and cold in all faucets. Turned on the hot water heater, it fired up ok. Everything is fine, hot water flame turned off when up to temp. Went to sink, turned on hot water faucet and just a dribble of water. What to do??? So I shut off the hot water tank switch so it wouldn't fire up, and proceeded to slowly remove the drain plug. (Remembering sometime ago about the tank needing an air bubble inside to operate properly). I drained the tank to about half empty and re-installed the plug. Turned on the water at the hose. Checked for flow at the sink and had it. (Cold water out of the hot faucet). Turned on the (switch) for the hot water tank. It fired up as normal. When hot and up to temp. it shut off. Now checked for flow and got a trickle again!
What am I doing wrong here? Has anyone had something like this happen to them?
Thanks for any and all help.

[Flintstones Adventurer]

This past week-end my hot water tank was determined to get my attention, and so it did.

Upon arriving at the campsite, and hooking up the water hose, everything seemed fine. Good flow in both hot and cold in all faucets. Turned on the hot water heater, it fired up ok. Everything is fine, hot water flame turned off when up to temp. Went to sink, turned on hot water faucet and just a dribble of water. What to do??? So I shut off the hot water tank switch so it wouldn't fire up, and proceeded to slowly remove the drain plug. (Remembering sometime ago about the tank needing an air bubble inside to operate properly). I drained the tank to about half empty and re-installed the plug. Turned on the water at the hose. Checked for flow at the sink and had it. (Cold water out of the hot faucet). Turned on the (switch) for the hot water tank. It fired up as normal. When hot and up to temp. it shut off. Now checked for flow and got a trickle again!
What am I doing wrong here? Has anyone had something like this happen to them?
Thanks for any and all help.

[Wizard]

Not sure about the only when hot part, but when we had reduced flow, it was due to a defective check valve. Winnebago puts an inlet and outlet check valve on most water heaters for winterizing.
I had to replace the outlet check valve and found a calcium build up in the valve. I've had other people tell me that they put a gallon of vinegar in the tank and let it stay a few hours with the water hot to dissolve the calcium. Didn't help me any but may help you.
Good luck.

[Ron and Patti]

is it possible that you didnt switch over your diverter valve to normal and it is on divert from being winterized.

[KE0M]

Oh Fred - I am afraid I have some bad news for you. There are 2 types of RV'ers: those who have had check valve problems and those who will. Your hot water system has two check valves. One is on the cold water inlet to the tank and another on the hot water outlet on the tank. The factory puts them in the lines to keep antifreeze out of the tank when you winterize. One or both of your check valves is stuck. I removed both of mine and with great ceremony threw the guts of each into the Sea of Cortez. I reinstalled them and have not had and will not have hot water flow problems ever again. The only problem is, they are a real PIA to: A. Find B: Remove C: Repair or replace D: Reinstall (without leaks). I found one valve under and behind the tank behind an access cover plate held on with about a dozen screws. I found the second one on the other side of the coach, in the water service compartment, behind a cover plate that also had a dozen screws and I had to break a weld to get that plate off.

I do not use antifreeze to winterize - I use compressed air. Therefore, I don't need the check valve function and I feel confident now that both are disabled. Others will argue with me saying they want to use the antifreeze so they will need to put in new check valves. OK put in new ones but when are they going to be in the mood to remove and replace again at some time in the future. That's not my idea of "recreational."

Good luck.

Best regards,
Larry

[MrTransistor]

FYI
This is the old valve.

The new valve is shown center and left, old is on the right. All metal, no plastic.
http://www.irv2.com/photopost/data/5...n_the_left.JPG
Much better design, but not supplied by Winne.
See also this previous post.
Water heater check valve

[bellsharbor]

Yep! Just replaced my hot water check valve last week. Did the same thing.

[Izzyblueye]

Yep, its your check valves. Just paid $180.00 to have mine replaced. Wish I had them install manual valves for winterizing. Even that would be tough to access in my coach.

[Flintstones Adventurer]

Thanks everyone for the advice. Looks like I have a job ahead of me

I do the same as Larry (KEOM)I use air pressure to blow out the lines in the fall, so I see no need for the outlet check valve. I plan on removing it in the next week or so.

Thanks again everyone for all the advice.

[Flintstones Adventurer]

Well here is the update to my "low flow hot water problem". Such a small access behind the tank where the by-pass valve is located that there just was no way to get at the check valves. So with the breaker box directly next to the opening and behind the hot water tank, why not try to remove it? A few screws removed and the breaker box slid out of it's cubby hole. Yep, can see the rear of the hot water tank, but still won't be able to get to the check valves.

Outside I go, screw gun in hand. An hour later the hot water tank is out on a work platform next to the MH. Didn't want to completely remove it as the engine coolant lines are still attached.
Now I removed the outlet side check valve. Could instantly see the check valve stem and seat showing wear. Removed this and put the valve back on the tank. Checked the water inlet and it looked good as new, so I left it in place. Hope this decision won't be a mistake.

So in conclusion, after 4 hours of working on this project, and a few choice words expressed on how well I enjoyed this job, the tank is re-installed.

Will give it the water test tomorrow. Keep your fingers crossed for me this all works.

I took a few pictures but don't exactly know how to post them.

[KE0M]

Good morning Fred - for those of us who have "been there" our hearts go out to you. Yes, it is a tough job and I guess the probability that the problem is fixed is approximately 50% since there is one other check valve remaining. In my case, Murphy's law followed me throughout the project. To paraphrase, "which ever check valve has been removed, repaired, and replaced, it will then be obvious it is the other check valve which has failed." If you have a full flow in the hot water line, that is good news and bad news. How long will it be until the other check valve sticks shut? I am still an advocate of getting both of them disabled. Good Luck.

Larry

[Izzyblueye]

Flinstones Adventurer: Got to hand to you for taking the water heater out yourself. How much will the Motor Aide hoses allow you to escape the little bin.
I think I would have replaced the check valves with some sort of manual valve system for winterizing. I sure wish I had done that when I had a dealer replace mine. There are two of the check valves and they are a PIA ongoing problem. Got to hand it to you for doing the job yourself.

[Flintstones Adventurer]

Thanks Homer, and to all for the information. The motor aide hoses will reach outside the MH when the tank is removed. So that's good news if and when you need to replace the tank. We don't want anti-freeze fluid inside the MH.

After working 9 hours today, I arrived home to "work for myself!" Went right to the MH to re-connect the water supply and hot water lines to the back of the hot water tank. Had DW stand by the house faucet just in cast of a leak. Turned on the water.....no leaks. Fired up hot water tank, waited until it shut off and turned on a hot water faucet in the MH. PERFECT! No Leaks, No Runs, No Errors! (OK folks, here is where we all knock on wood)
[IMG]C:\Documents and Settings\Fred Hagedorn\My Documents\My Pictures\Camper Hot Water Tank\IMG_0050 (Small).JPG[/IMG]

[Flintstones Adventurer]

Woops....sorry for the lack of the image. Tried to upload a picture of the tank outside the MH. Didn't work.
I went to the photo site on this forum, of course I lost my pass word so I'm asking for the administrators to email it to me.