Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Plumbing

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 09-15-2013, 04:46 PM   #61
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,833
Share |
Default

Hot water from cold pipes, plumbers are stumped


Quote:
As Sureshot stated, that seems unlikely to make any difference since the recirc pump adds a relative pressure to the hot water, so both would increase. And I should mention that for different reasons, I did increase the cold water pressure from 60psi to 70psi many weeks ago, but it had no impact on the problem.
Did you check if hot water is getting into the cold line from the recirc pump. Its check valve may not seat all the time.

__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
Old 09-15-2013, 04:50 PM   #62
Newbie
 
Join Date: Jul 2013
Posts: 26
Default

Hot water from cold pipes, plumbers are stumped


Quote:
Originally Posted by beenthere View Post
Did you check if hot water is getting into the cold line from the recirc pump. Its check valve may not seat all the time.
After the problem started, I hired plumber #1, who replaced the old (noisy) recirc pump with a fancy new one that has a built-in check valve. The problem persisted.

So I believe that the HW check valve is not to blame. Also, the old pump ran all the time, in which case I think a check valve is irrelevant. The new pump has a timer and thermal sensor, so the check valve has a chance to matter. But again, the problem predates this fancier pump.

/Seabeast
seabeast is offline   Reply With Quote
Old 09-15-2013, 04:58 PM   #63
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,833
Default

Hot water from cold pipes, plumbers are stumped


I was referring to the check valve that should be in the cold water line. To prevent the hot water from being pushed into it.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
Old 09-15-2013, 06:14 PM   #64
Member
 
Join Date: Mar 2013
Location: Ohio
Posts: 2,146
Default

Hot water from cold pipes, plumbers are stumped


Just for giggles sea beast could you turn off the cold to the hot water tank. Turn off the recirculation line hope it has a valve. Then open up the KS faucet hot only and see if it has any pressure after 3 or 4 minutes. It will take time to bleed off your expansion tank. Also turn your pump off on the recirculation line.

If the hot still has pressure then we are dealing with a cross connection and a Delta can do this. And your washer machine can also.
Ghostmaker is offline   Reply With Quote
The Following User Says Thank You to Ghostmaker For This Useful Post:
seabeast (09-24-2013)
Old 09-15-2013, 06:31 PM   #65
moderator
 
TheEplumber's Avatar
 
Join Date: Jul 2010
Location: Idaho
Posts: 6,775
Default

Hot water from cold pipes, plumbers are stumped


Quote:
Originally Posted by Ghostmaker View Post
Just for giggles sea beast could you turn off the cold to the hot water tank. Turn off the recirculation line hope it has a valve. Then open up the KS faucet hot only and see if it has any pressure after 3 or 4 minutes. It will take time to bleed off your expansion tank. Also turn your pump off on the recirculation line.

If the hot still has pressure then we are dealing with a cross connection and a Delta can do this. And your washer machine can also.
Have you done a 180 on this? I feel a faucet/mixer is the issue as well.
Or it could be as BT suggested, this thread is long and old- so many suggestions laid out but I can't remember whats been confirmed.......
__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions
TheEplumber is offline   Reply With Quote
The Following User Says Thank You to TheEplumber For This Useful Post:
seabeast (09-24-2013)
Old 09-15-2013, 09:29 PM   #66
Newbie
 
Join Date: Jul 2013
Posts: 26
Default

Hot water from cold pipes, plumbers are stumped


Quote:
Originally Posted by beenthere View Post
I was referring to the check valve that should be in the cold water line. To prevent the hot water from being pushed into it.
Until about two weeks ago when I had a plumber install one, there was no check valve on the cold water line. So not sure what you mean by "should be there". There is one now, but never was one before, even way back when things worked properly.

But you do raise a good point: if the newly-installed check valve were failing to properly block reverse flow sometimes, that could explain the "sometimes" nature of the problem now.

I never actually got a good look at the check valve before the plumber installed it. He used a spring valve, rather than a swing gate valve as I had seen elsewhere.

The spring ball check valves seems pretty foolproof, though. Is this a plausible failure scenario?

/Seabeast
seabeast is offline   Reply With Quote
Old 09-15-2013, 09:48 PM   #67
Always Learning
 
Join Date: Sep 2013
Location: Saskatchewan
Posts: 7
Default

Hot water from cold pipes, plumbers are stumped


I think the sometimes is the cold water usage. The problem is occurring at a junction of the hot and cold lines and can only happen when you have a pressure differential. So if your sprinklers are on a timer for 5AM and you get up at 7AM the "condition" has existed for 2 hrs and is noticeable. On days when someone turns on the shower and leaves it run a few seconds before testing the temp the condition goes undetected. The system is not that complicated so the solution shouldn't be either.
Is this a home run system or branch circuit or whatever they call it?
Is it just one tap or all of them?
Many pieces missing and some controlled testing needs to happen.
Try starting the sprinklers hours before the family rises and test each tap for the volume if any of hot that comes from it. That will narrow the problem. I suspect a check valve on the cold at that fixture will end the problem.
Is the water instant hot at the fixture when turning on the cold or starts cold and gets hot then goes cold. I suspect starts hottest and cools to normal cold in time telling you it is leaking through the fixture.
If it were way back at the tank it would have to displace the cold water from the line to replace it with hot. So where is the cold going if that is the case?
I think it is time to step back, clear the head, and take a fresh look and collect better data. JMHO.
Sureshot is offline   Reply With Quote
Old 09-15-2013, 11:04 PM   #68
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,833
Default

Hot water from cold pipes, plumbers are stumped


Quote:
The spring ball check valves seems pretty foolproof, though. Is this a plausible failure scenario?
Yes it is.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
Old 09-16-2013, 06:54 AM   #69
Member
 
PoleCat's Avatar
 
Join Date: Sep 2009
Location: Dayton, Ohio
Posts: 1,375
Default

Hot water from cold pipes, plumbers are stumped


Having read the whole thread it would appear that there is something about the new water heater that is the culprit. But that just doesn't add up no mater how you try to imagine it. It still comes back down to the observations made so far:
  1. Problem only occurs while recirculation pump runs.
  2. All fixtures are ambient temperature until turned on.
This implies that the cold water pipe is acting as the return either alone or in tandem with the intended return. To verify this I would go to the trouble of installing another ball valve on the cold line that supplies everything BUT the water heater. While this is shut off the only place water can flow is through the water heater and recirculation loop. Try some fixtures with separate valves(toilets, faucets, hose bib) If you get any water pressure from the cold you have proved there is clearly an open cross over somewhere.

Is it possible the water heater replacement may have involved some pipe modifications where the return line may have been mistaken for a supply line and re connected wrong?
__________________
"Ask me anything. If I don't know the answer I'll make something up."
PoleCat is online now   Reply With Quote
Old 09-23-2013, 02:47 AM   #70
Newbie
 
Join Date: Jul 2013
Posts: 26
Default

Hot water from cold pipes, plumbers are stumped


Quote:
Originally Posted by Ghostmaker View Post
Just for giggles sea beast could you turn off the cold to the hot water tank. Turn off the recirculation line hope it has a valve. Then open up the KS faucet hot only and see if it has any pressure after 3 or 4 minutes. It will take time to bleed off your expansion tank. Also turn your pump off on the recirculation line.

If the hot still has pressure then we are dealing with a cross connection and a Delta can do this. And your washer machine can also.
Bingo!

So, there was a breakthrough this weekend. Last week my son complained that he couldn't get hot water out of his shower anymore. So on Saturday I decided to replace the faulty valve. But before removing it, I tried Ghostmaker's suggestion and turned off the input to the water heater and the recirculating pump. Sure enough, the hot faucets in the house still had a pretty decent flow. And when I went upstairs to my son's bathroom, the shower valve in question was making the loud "woosh" sound of running water. Clearly that valve was a crossover point.

And here is also where I need to admit that I was wrong in something I stated previously: not all of our faucets are Delta. Turns out my son's shower (and probably 1 other upstairs shower) uses Price Pfister valves. And it seems the pressure balance valve failed in a way that let hot and cold mix.

After replacing the valve, our problem finally seems to be fixed. Strangely, even after fixing this valve I still get water from the hot taps when the hot water heater is cutoff from the supply. I read elsewhere that pressure balance valves can do that when one side has no pressure at all, so I'm not too worried, but a little.

So, finally I found an explanation for my problem that makes sense. After four plumbers, over $1000 spent on "improvements", and countless hours, it seems a $20 part was all I really needed...

Interestingly, our hot water seems a lot hotter now. Guess we were also really getting a lot of cold-into-hot mixing at that valve.

Thanks everyone for your help and support!! Hope this massive thread helps another poor soul someday...

-Seabeast
seabeast is offline   Reply With Quote
Old 09-23-2013, 04:24 AM   #71
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,833
Default

Hot water from cold pipes, plumbers are stumped


I think a bad shower faucet was suggested back in post number 2.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
The Following User Says Thank You to beenthere For This Useful Post:
oh'mike (09-23-2013)
Old 09-23-2013, 05:43 AM   #72
DIY staff
 
Join Date: Sep 2009
Location: Kane county,Illinois
Posts: 21,485
Default

Hot water from cold pipes, plumbers are stumped


EPlumber gets the pot---

Glad you found the solution--Mike---
__________________
New members: Adding your location to your profile helps in many ways.--M--
oh'mike is online now   Reply With Quote
Old 09-23-2013, 10:05 AM   #73
Newbie
 
Join Date: Jul 2013
Posts: 26
Default

Hot water from cold pipes, plumbers are stumped


No, Ghostmaker gets the prize. The shower valves were a suspect before I even posted here, as mentioned in post #1. That's why I had the first plumber check them.

Ghostmaker was the first to suggest an experiment that actually identified the culprit.

Ever see those signs in car shops that say something like "Parts $20, labor $20, knowing which part to replace $500." That was pretty much my situation.
seabeast is offline   Reply With Quote
The Following User Says Thank You to seabeast For This Useful Post:
oh'mike (09-23-2013)
Old 09-23-2013, 10:58 AM   #74
Always Learning
 
Join Date: Sep 2013
Location: Saskatchewan
Posts: 7
Default

Hot water from cold pipes, plumbers are stumped


See also post #57. There might be some discrepancy as to what "disconnect" means but I meant physically disconnect it.
Ghostmaker's plan found it with less mess for sure and is a good thing to keep in mind. A person could use an IR gun and even find slower leaks by running hot through each fixture until hot then shutting the pressure off to the cold other than the water heater and "looking" for the heat moving into the cold side with a cold faucet open. In your case with the circ pump you would't need to run the hot as it is always there.
Sureshot is offline   Reply With Quote
Old 09-23-2013, 05:34 PM   #75
DIY staff
 
Join Date: Sep 2009
Location: Kane county,Illinois
Posts: 21,485
Default

Hot water from cold pipes, plumbers are stumped


Thanks for identifying the method used to find the problem----

Ghost maker wins the pot-----

__________________
New members: Adding your location to your profile helps in many ways.--M--
oh'mike is online now   Reply With Quote
The Following User Says Thank You to oh'mike For This Useful Post:
seabeast (09-24-2013)
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
insulating cold water pipes joefromcal Plumbing 8 06-06-2013 12:11 AM
Trickle of Cold Water Pioneer Bathtub Faucet egawrons Plumbing 0 10-25-2012 11:24 AM
Warm Water out of Cold Water Outlet mb0709 Plumbing 9 08-26-2012 12:59 PM
Solar hot water indatom123 Green Home Improvement 0 12-19-2010 12:01 AM
hot n cold water pipes in bath vanity handekaps Plumbing 4 01-10-2010 09:49 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.