No Hot Water ...

DriVer · 01-07-2005, 03:31 PM

Captain Bud is having a problem with his water heater.

1. It fires up on both electric and gas, OK
2. It fills with cold water.
3. It heats and then shuts down the flame having met the high limit.
4. It spews air out of the hot water side of the faucet when opening the faucet.
5. It flows water from the hot side of the faucet, but always cold.
5a. The exception is that it spurts out a tiny amount of warm water for a fraction of a second.
6. Dismantled the line to the cold water relief valve, works OK Cap'n Bud got a face full.
7. The normal and bypass valve was ruled out by exchanging valve with the winterizing valve, works same guts.
8. Tried to operate the system using the water pump, same results.
9. Drained and refilled the tank at least twice

The problem is that no matter what we do we can't flow hot water out of the water heater! We know that there is hot water in the heater because it's hot when opening the relief valve.

Both suggestions have not panned out. Bad check valve (lower of tank) and bad diverter valve (ruled out).

Any ideas folks?

DriVer · 01-07-2005, 03:31 PM

Captain Bud is having a problem with his water heater.

1. It fires up on both electric and gas, OK
2. It fills with cold water.
3. It heats and then shuts down the flame having met the high limit.
4. It spews air out of the hot water side of the faucet when opening the faucet.
5. It flows water from the hot side of the faucet, but always cold.
5a. The exception is that it spurts out a tiny amount of warm water for a fraction of a second.
6. Dismantled the line to the cold water relief valve, works OK Cap'n Bud got a face full.
7. The normal and bypass valve was ruled out by exchanging valve with the winterizing valve, works same guts.
8. Tried to operate the system using the water pump, same results.
9. Drained and refilled the tank at least twice

The problem is that no matter what we do we can't flow hot water out of the water heater! We know that there is hot water in the heater because it's hot when opening the relief valve.

Both suggestions have not panned out. Bad check valve (lower of tank) and bad diverter valve (ruled out).

Any ideas folks?

Easyrider · 01-07-2005, 05:47 PM

I'm not a plumber but it sounds like something is wrong with the mixing valve on the faucet. You're just barely getting some warm water and then the cold takes over. It can't be the heater based on what you have told us. I assume you have a single handle faucet and think you should take it apart and see if everything inside is assembled correctly or just remove faucet and replace with a new one.

Barney B. · 01-07-2005, 05:57 PM

It seems to me that if the heater bypass valve is working correctly and the water heater is actually heating the water and not just limiting out for some other reason then there is no way that "cold water in" won't equal "hot water out".

Either the bypass valve is bad or you've got a tank of cold water. Have you opened the pop-off valve to make sure the water is hot?

Barney B. · 01-07-2005, 06:02 PM

Oops, I see you already tried the pop-off valve. Next time I'll "read for content".

BucknJeff · 01-07-2005, 06:43 PM

There are check valves in the inlet AND outlet of the water heater. Check the check valve in the line of the HOT OUT of the heater. I Think that may be the problem.

Also, does he have auto-winterization?

Hope this helps!

JB Texas · 01-07-2005, 06:49 PM

I had a similar experience in my old Southwind. Couldn't get hot water to kitchen, only lukewarm. The problem was I had left the outside shower hot and cold water turned on at the knobs and shut off at the shower head. The shower control was acting as a mixing valve.

3huskies · 01-08-2005, 03:39 AM

If he has any single handle faucets, sometimes the valve assemblies get worn inside and while they don't drip, they may bypass cold water into the hot pipe and out another faucet.
As JBWLMS stated check both inside and outside showers to be sure they are shut off at the faucets and not the head.

3huskies · 01-08-2005, 03:52 AM

One other thought. If you can feel the hot and cold water lines to the faucet(s) you may be able to determine where the problem is.

DonavonP · 01-08-2005, 04:21 AM

My thought is that the outside water faucets were refilled with fresh water during the winterization process. Unintentionally of course, but they were probably the first ones to be checked for the antifreeze and then shut off to proceed to the rest of the faucets and fresh water drained back into the valve.They froze, and are now causing your problem. Try removing the hot water cassette from the outside shower valve and see if you get hot water through the hole.

DriVer · 01-08-2005, 03:06 PM

and the answer is ....

The "top (HOT) check valve" on the Atwood 10 gal DSI heater.

Bud had it up to here so he called in an RV tech. What was found that the valve's spring was missing. There was no spring backing up the valve and what would happen is that the back pressure on the cold water side of the check valve forced or kept the valve closed not allowing the cold water to flow into the heater except when initially turning on a hot water faucet. The valve effectively blocked the flow of hot water from the heater tank.

We got a short spurt of hot water and that was it.

When the RV tech installed a new hot water check valve on the top of the heater the system worked perfectly. I was heading in this direction myself but I don't know much about the mechanics of how the water heater system works.

Well about that, let me say this. Beginning with my most recent experience with the water heater diode and figuring out all the 12 volt side of the heater I now have a school of hard knocks education about how the heater is plumbed.

We took a Sharpie and put arrows and hot and cold descriptions on all the lines in the compartment so we could reason the water flow and we had it all correct.

We were advised that the heater only had 1 check valve however we found that to be inaccurate. There are 2 check valves. We were also advised that it could be the diverter valve but we ruled that out.

Well Ruth is certainly glad to have her hot water back and so is Bud.

The closest problem resolution was submitted by: BucknJeff

Thank you!

BucknJeff · 01-08-2005, 06:27 PM

Glad my guess won!

It's important to remember that the check valves are there, in part, to facilitate the winterization bypass function. When they fail, we may be tempted to remove them. You can, but the bypass may not function properly without them installed.

Glad it helped.

pleeds · 01-12-2005, 09:52 PM

Hi Gang:

We had the same "lack of hot water at faucet" problem on initial trip in our rig. After three days of not being able to take a hot shower took the unit to a Salt Lake City dealer. In one hour dealer determined that check valve on BACK of water heater had been factory installed backwards. We would have never gotten hot water out of that tank. How much are those assemblers at the factory making???

Moral...when doing the PDI at dealership make them demonstrate that hot water will flow....

Best,

criscriscola · 01-13-2005, 02:13 PM

Same thing happened to me as you can see on the forum. I fooled with it for 3 days, replacing on/off rocker on back of water heater ( NEEDED) still no water coming out of faucets on hot water side. Started pulling out check valves in back of heater< ( A BUGGER BEAR) no room. Anyway got them pulled and both check valves were defective, after gutting them of springs and little plastic joberoonies looking like golf tees, everything worked fine. Figured I saved myself about $300. for a tech. I understand that the only purpose they serve is for Winterizing, The only way I winterize is to go South every year, so Oh well. Keep up the good work, the FORUM is better than sliced bread.
cris criscola
02 Suncruiser 35U/W22
04 Vue/Blueox

RKL2 · 03-03-2005, 04:33 PM

Driver..per my post today I can not get cold water to flow into the waterheater tank...after draining the waterheater still no water flowed into the tank...on bypass cold water comes out of the hot water faucet before emptying tank) but no water comes out when in regular mode...Winne tech said on the Journeys in 2002 a check valve was put in the line to the WH in the water pipe closet by the fill as it was impossible to get to the previous check valve installed in the Journeys as the waterheater is below the floor behind the pass side rear tire and is builtin so no water lines show... I looked at the 2002 plumbing diagrams and no where does it show a check valve at the water closet location....any insite would be appreciated....thanks RKL

DriVer · 03-03-2005, 05:50 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by RKL:
...any incite would be appreciated....thanks RKL </div></BLOCKQUOTE>Perhaps Joe-K or Tomcat F15 will share some incite with you about the check valve location.

My check valves are mounted close to or on the heater tank and on a 38G are very difficult to work with.

Joe-K · 03-04-2005, 06:44 AM

RKL,

I posted some thoughts and detalis in your other thread about the problem.

I agree with you. The prints show the check valve is at the water heater. As I mentioned in the other thread, you might be able to look into the water line closet by removing the bottom drawer in the bedroom chest of drawers. There is an opening there that opens to the water closet. It'll take a mirror and flashlight, but you can look around for a problem without tearing the water line closet panel off.

RKL2 · 03-05-2005, 01:28 PM

Cold water now going into waterheater....It was the checkvalve on the cold water intake..Camping World didn't have a replacement so we removed the guts and reinserted the brass fitting. Don't have to worry about bypass or winterizing as we are snowbirds...Learned how to bypass the automatic electric bypass if it fails. just move 2 hoses in the watercompartment...thanks for your insite....RKL