WHY does this happen ??? - Page 2 - Montana Owners Club

Thunderman · 10-07-2004, 11:54 AM

I wonder if a larger supply line from the hot water heater to the shower would solve this problem?

DiananColin · 10-07-2004, 03:14 PM

Did nobody realise that this is a positive! Prince Charles found out the hard way that Gordonstoun may have been a VERY expensive school but they insisted on COLD showers for the students every morning! This sort of toughening up comes for free with your fiver!

I'll still turn the shower head away and keep it on - I'm not hardened to this sort of torture; I like it warm!

Trailer Trash 2 · 10-07-2004, 04:07 PM

babtmakers3. It sounds like a sound answer, I was thinking of putting a backcheck on the hot water supply line and see what happens, I'm surprised there are no plumbers out there that can give a good answer to the question, Oh! I did ask my Division Manager who is or was a plumber, and here was his answer. " I have the same problem, I just turn the shower head to the wall and wait for it to get hot again". I dont know, even a plumber has to turn the shower head too.

TT2

On The Road Again · 10-14-2004, 12:41 AM

We've never had this problem...yet. I'll surely be testing it next week on our trip to the mountains of Virginia. Normally, we just let it run, unless boondocking, and take a quick shower and don't (yet) run out of hot water. Our hot water heater is next to our entry door, so is very close to the shower.

Merv · 10-14-2004, 09:56 AM

TRAILER TRASH 2,
I THINK YOU ARE ON TO THE ANSWER. I BELIEVE THE WATER HEATER HAS A BACKFLOW VALVE BUILT INTO THE "OUT" LINE. I DONT THINK IT WORKS VERY WELL THOUGH. I THINK WHAT IS HAPPENEING IS THAT THE COLD WATER FORCES ITS WAY INTO THE WATER HEATER THROUGH THE OUT LINE. WHEN YOU TURN ON THE WATER AGAIN, IT MUST FIRST FORCE OUT THE COLD WATER THAT FILLED THE HOT LINE. THEN THE HOT STARTS COMING AGAIN. A BETTER BACK FLOW VALVE SHOULD DO THE TRICK.
JUST MY THOUGHTS ON THE MATTER, I HAVENT ATTEMPTED FIXING THIS YET.
MERV

Montana_31 · 10-15-2004, 02:15 AM

Ours does the same thing except the water comes out hot when we turn it back on.

Dennis and Carol · 10-15-2004, 06:39 AM

I do not know if there is a check (backflow) valve on the hot water tank. When I winterized ours last week, I could not get a good look at the plumbing around the H/W tank. I was able to determine that when the bypass valve is changed, it routes the water toward the top of the tank and then on to the hotwater lines in the trailer. Normally, the cold water enters the H/W tank at the bottom and the hot water exits at the top. I think the problem is with the mixer valve on the shower rather than the shower head. Seems like it did it even if the shower head was only turned off for a few seconds. Our previous TT also had the same problem, probably a function of cost to manufacturer.

tnorfitz · 10-23-2004, 03:00 PM

Try the same thing at your home, if your shower head has this capacity. Most don't. You will find that the water that is not flowing will cool down. The longer the shower head is turned completely off, the more the temperature will cool off. Have you ever noticed that the shower temperature gets slightly warmer at the beginning, when you first get in. The water is getting warmer because it is heating up the supply line as it is going through. The more hot water run through the line, the warmer the temperature gets at the point of release, until the time that the water line is at the same temperature of the water flowing through it. When there is a interruption of the hot supply, the line, and the water in it, will try to cool down the the temperature around it, although not very quickly.
The hotter you take your shower, the cooler the temperature will feel when you turn the shower head back on. Hence, a lower temperature shower will not feel as cold when you turn the water back on as a hot shower will!!! You are not expecting the water to cool off for that little bit of time, but it does.
Another thing. The water, waiting to get from the hot water heater to the shower head, is run through the basement area, which is generally a cooler area, especially in winter time!!! It will cool off much quicker while waiting for the water to push through again!!! Your hot water heater in your home is usually located in an area that is more room temperature, and the supply lines to the shower knobs are not subject to as much cooling as the hot water supply line area in the RV. You may not notice as much of a temperature drop by doing this at home. Seems to be much more noticable in RV's!
Remember, it is not just the hot water lines cooling down either. In cooler weather, the cold water feed is ground temperature. If the outside air, as well as your basement area, is cooler than the water temperature coming out of the ground, the cold and hot water lines are both cooling down in your basement area, creating that chilling effect. In summer time, the temperature drop should not be as noticable because the basement area will be warmer.
Just my thoughts

Jim Fitzpatrick

sreigle · 10-23-2004, 06:54 PM

Quote:

quote:Originally posted by DiananColin

Did nobody realise that this is a positive! Prince Charles found out the hard way that Gordonstoun may have been a VERY expensive school but they insisted on COLD showers for the students every morning! This sort of toughening up comes for free with your fiver!

I'll still turn the shower head away and keep it on - I'm not hardened to this sort of torture; I like it warm!

LOL! This has to be Diana talking, right??!!

Thunderman · 10-26-2004, 04:56 PM

On another forum, one person reportedly put a brass check valve in the hot water line and solved this problem. Brass check valve and fittings at Lowes or Home Depot about $10.00.
An easy fix if it works.

Northstar · 10-26-2004, 09:52 PM

Sounds like a good idea. I will keep this in mind for later. Happyrving....

steves · 10-29-2004, 05:31 AM

I have the solution.....just shower once a week and it won't be that big a deal. Sorry I couldn't help myself. I too have the same problem but in my previous unit (a Sunnybrook) I didn't have the problem so it's something in the plumbing design.

Steve S

sreigle · 10-29-2004, 05:47 PM

Steve, I'd like to hear Betty's comment on your idea!

tnorfitz · 10-30-2004, 03:39 PM

I bet Betty would say "That idea stinks!"

sreigle · 10-30-2004, 04:27 PM

or "smells to high heaven".

rames14 · 11-01-2004, 04:34 PM

What was the size of the check valve and where in the supply line did you install it (basement or by the hot water tank)? Inquiring minds want to know. I don't think that the water can cool that rapidly. I also turn it toward the wall and let it run a few seconds but when you're boondocking every ounce counts.

Thunderman · 11-02-2004, 04:12 AM

Quote:

quote:Originally posted by rames14

What was the size of the check valve and where in the supply line did you install it (basement or by the hot water tank)? Inquiring minds want to know. I don't think that the water can cool that rapidly. I also turn it toward the wall and let it run a few seconds but when you're boondocking every ounce counts.

Ron,
I think the check valve was 3/4 and installed in the line right above the hw heater. This info was picked up on RV.Net

Montana_1197 · 11-03-2004, 04:28 PM

I ran this

item past a RV tech today and he said that the few seconds of cold is because it takes a sec or so for the line pressure (remember it's a low pressure) to "push" the hot water out of the tank whereas the cold line is under a more steady pressure and responds quicker, thus the inital cold water hit. I asked about the cold water pushing back into the hot water line a little and although he admitted never checking that angle it wouldn't surprise him because of the little different pressure each line is under. If that's actually what is happening then a check valve would be effective. Makes sense anyway.

sreigle · 11-03-2004, 05:11 PM

Now that makes some sense. At least to this untrained mind. Thanks Don and Janey.

Jim B · 11-14-2004, 05:25 AM

When you winterize your trailers as I do every year you will find only one valve to shut off the in line to your hot water heater. This is a one valve by-pass system. The reason you only need one shut off valve is that there is a brass check valve in the out line of the hot water heater there by not allowing RV anti freeze to enter the tank. This should also prevent water from flowing back into the tank when you shut the shower head off. Every rig that I have had does the same thing when you shut off the shower head and turn it back on cold water comes out for a few seconds. I have changed shower heads which didn't make any difference. Does everyone realize that there is a restrictor in the shower head so you can conserve water. I removed the pink restrictor and it did make a little difference. 2004 2955RL.

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