(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 6 of 6

Thread: Hot water goes cold after a few seconds even after installing new water heater

  1. #1
    DIY Junior Member nemanich's Avatar
    Join Date
    Dec 2012
    Location
    CA
    Posts
    1

    Default Hot water goes cold after a few seconds even after installing new water heater

    Hot water would go cold after a few seconds. This was from all faucets in the home (small house - 1000 sq ft). Thinking it was the water heater, we have just replace with a Whirlpool water heater. Having the same problem.

  2. #2
    DIY Senior Member bluebinky's Avatar
    Join Date
    Aug 2011
    Location
    Santa Clara, CA
    Posts
    354

    Default

    Tankless water heater?

  3. #3
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,602

    Default

    Well, if you were in this area, I would tell you that you have a serious hot water leak under your concrete floor slab. I once knew a plumber whose customer had the same symptom and when a new heater did not cure the problem, he tried to return the heater because he said it was defective. I had to REALLY talk seriously to convince him the he DID have a water leak, and nothing would stop the problem until he found, and fixed it.
    Licensed residential and commercial plumber

  4. #4
    DIY Junior Member 6t7gto's Avatar
    Join Date
    Jan 2010
    Location
    Bedford, Ohio
    Posts
    46

    Default

    We thought we had a defective water heater. Called for service and he shut the supply off to the water heater. Waited a few minutes and turned it back on. You could hear the water running, filling the pipe that was leaking under the crawl space in the rear of the house.

    david

    p.s. maybe your new tank doesn't have a dip tube in it. or it is connected backward.
    Last edited by 6t7gto; 12-31-2012 at 12:03 PM.

  5. #5
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,602

    Default

    quote; maybe your new tank doesn't have a dip tube in it. or it is connected backward

    A "missing" dip tube is almost impossible these days because it is a part of the inlet nipple, (besides the improbability of it happening with both an old AND new water heater). If it were connected "backwards" there would be considerable hot water in the tank before the cold water reached the bottom of the dip tube to change the user's temperature. Diagnosing the cause is almost impossible without being there to see the conditions as it happens.
    Licensed residential and commercial plumber

  6. #6
    DIYer, not in the trades LLigetfa's Avatar
    Join Date
    Feb 2011
    Location
    NW Ontario, Canada
    Posts
    3,675

    Default

    Quote Originally Posted by nemanich View Post
    Hot water would go cold after a few seconds...
    Quote Originally Posted by hj View Post
    Well, if you were in this area, I would tell you that you have a serious hot water leak under your concrete floor slab...
    I would think that if there was a leak, the water would start out cold and stay cold, not start hot and go cold after a few seconds.

    Prognosis #1. A tankless unit with inadequate gas supply, exhaust balance issue, etc..

    Prognosis #2. A bad balance spool causing a crossover.

    Prognosis #3. A recirc loop gone bad.

    Like the early talking computers would say "insufficient data, does not compute"

Similar Threads

  1. Tankless water heater cold water line
    By prbearden in forum Tankless Water Heater Forum
    Replies: 2
    Last Post: 02-01-2012, 12:16 PM
  2. Cold Water Supply reduced to 3/4" before water heater...
    By speede541 in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 9
    Last Post: 09-02-2011, 12:38 PM
  3. Water heater question - cold water, water leaking thru overflow pipe
    By jonyi in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 6
    Last Post: 09-26-2009, 01:26 PM
  4. help hot water gets cold a few seconds
    By mekdek in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 1
    Last Post: 02-02-2008, 08:11 AM
  5. Hot Water Heater - hot water expanding back into cold pipes
    By uncoolcentral in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 5
    Last Post: 10-26-2004, 11:07 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •