hot water at pressure 125 - what does this say about 13yr hot water heater

Discussion in 'Plumbing Forum' started by montag, Apr 21, 2013.

  1. Apr 21, 2013 #1

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    Hi all,

    I have a tanked hot water heater, 13 years old, that I am thinking is reaching the end of it's useful life, but wanted to get some expert opinion before replacing.

    Current problem we are seeing
    Hot water is venting via a wilkins 1500 valve (graduated screw in type) from the hot water side of the tank, to a pvc pipe and then to outside. It's been doing this for a number of weeks. Currently the wilkins valve is set to 125.

    Note that this wilkins is inline with the hot water pipe exiting the tank and is separate from the TPR valve on the side of the tank. I don't know why I have this extra valve. I operated the TPR valve and it is working; vents when I pull it and stops when I release it.

    Anyways, since the wilkins is set to 125, is that a high or low pressure for hot water or do I have room to play to alter it to stop this venting? (perhaps dangerous given it's a safety valve).

    And what does this venting and the 125 value say about the health of the hot water heater?

    Note that we don't have any complaints about the temperature or pressure of hot water into the house.

    hot water heater details
    50 gallon, tanked
    model : PR6 5C NPRT971
    State Industries Inc, Ashland City, TN
    Original water heater install on new home 1999.

    Thanks
    mike
     
  2. Apr 21, 2013 #2

    JoeD

    JoeD

    JoeD

    Well-Known Member

    Joined:
    Mar 16, 2006
    Messages:
    1,528
    Likes Received:
    273
    put an actual pressure gauge on the system and see what the actual pressure is. Maybe the valve is failing.
     
  3. Apr 22, 2013 #3

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    Do you mean measure the hot water pressure. How would I that since I am only familiar with the pressure gauges that fit on an outside faucet for the cold water. I guess I could cut in and add a suitable connector to one of the hot water pipes and measure from that.
     
  4. Apr 22, 2013 #4

    nealtw

    nealtw

    nealtw

    Contractor retired

    Joined:
    Nov 4, 2010
    Messages:
    23,902
    Likes Received:
    3,121
    that type of gauge would work on the tap for the washing machine.
     
  5. Apr 22, 2013 #5

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    That's a great tip. I didn't think of the washing machine connection :confused:. Thank you. Just need to a gauge now from hd or lowes.
     
  6. Apr 22, 2013 #6

    JoeD

    JoeD

    JoeD

    Well-Known Member

    Joined:
    Mar 16, 2006
    Messages:
    1,528
    Likes Received:
    273
    The cold water should also be at the same pressure. Everything on the system should be at the same pressure. I suspect a failing valve or the TPR would be releasing also.
     
    nealtw likes this.
  7. Apr 22, 2013 #7

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    Thank you JoeD. I'll check the pressure on both hot and cold and post the results.
     
  8. Apr 22, 2013 #8

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    I got a basic water pressure test gauge from Lowes (orbit model #91130) and tested both the hot and cold lines for pressure.

    With no faucets on or any other items drawing water, cold is at 98psi and hot (or not so hot since its not really running at the time of test), at little over 100psi. So not good.

    Could it be my Pressure Regulator Valve is faulty and not stepping down the pressure from the street? I should also have mentioned that when we have two faucets on at the same time and we get a wining sound from the plumbing. It doesn't bang, just a whine, medium pitch.

    I plan to get a second, better test gauge later this week since I don't think I should rely on one test and one gauge. Will get something more robust from a professional plumbers supply place - just can't get there today with work etc.

    As for my location, and I only mention this because the Lowes guy asked, am located in Cobb County, suburb of Atlanta and Lowes guy said my pressure should be around 45-50 something.
     
    Last edited: Apr 22, 2013
  9. Apr 22, 2013 #9

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    Some additional info from my testing.

    With the test gauge attached to the cold line it reads 98psi with no faucets or water being drawn. If I turn on a faucet on the same floor as the gauge, the pressure drops to 40psi. Then turn off the faucet and the pressure climbs back to 98psi and takes about 30-60 seconds.
     
  10. Apr 22, 2013 #10

    nealtw

    nealtw

    nealtw

    Contractor retired

    Joined:
    Nov 4, 2010
    Messages:
    23,902
    Likes Received:
    3,121
    If you have a pressure reducing valve near the shut off valve you can take that down to about 60lbs and I think Joe is right about replacing the pressure release valve on the water tank.
     
  11. Apr 22, 2013 #11

    JoeD

    JoeD

    JoeD

    Well-Known Member

    Joined:
    Mar 16, 2006
    Messages:
    1,528
    Likes Received:
    273
    98 psi is too high. Most fixture will have a max rating of 80 psi and 40 to 60 is sufficient for most homes.
    I think if you have a pressure regulator on your main line then it is defective. probably a hole in the diaphragm by the 30 second rise from 40 to 98.
     
  12. Apr 22, 2013 #12

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    Thanks Neal. Sorry to be dense but do mean replace the TPR valve on the side of the water heater or replace the wilkins valve on the hot water line. I'm thinking you mean the TPR because it should be releasing water with this high pressure problem and it is not. The wilkins valve is doing the release, thankfully. The pipe to the wilkins is warm and I can hear it running and the pipe to the TPR is cold with no running sound.

    I do have a pressure reducing valve (cone shaped thing) at the point where water comes into the garage (where the water heater is located). I adjusted it counter clockwise a number of turns and it had very little effect on reducing static pressure. Only went down by 2lbs. Did at least 5 turns so it backed out a distance of 5mm. I'm afraid to back it out any more.
     
  13. Apr 22, 2013 #13

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    I think you are right Joe. The pressure regulator is not working and has to be replaced. A job for this weekend.
     
  14. Apr 23, 2013 #14

    oldognewtrick

    oldognewtrick

    oldognewtrick

    Administrator Staff Member Admin Moderator

    Joined:
    Jul 26, 2009
    Messages:
    10,820
    Likes Received:
    1,435
    After you turned the regulator back, did you run water to relieve the pressure in the pipe?
     
    nealtw likes this.
  15. Apr 23, 2013 #15

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    I saw a video online that said to run a faucet slightly while making the adjustment, so I did that. After I did the adjustment I turned on the faucet full for 10 seconds then closed it and went and checked the static water pressure.
     
  16. Apr 23, 2013 #16

    nealtw

    nealtw

    nealtw

    Contractor retired

    Joined:
    Nov 4, 2010
    Messages:
    23,902
    Likes Received:
    3,121
    I would change both, the regulater and the release valves.
     
  17. Apr 23, 2013 #17

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    Thanks Neal. Will change both the reducing and TPR valve.

    Just for reference, I've attached an image of the existing reducing valve. Will try and get one of similar dimensions.

    pressure_regulator_valve_042213_small.jpg
     
  18. Apr 23, 2013 #18

    CallMeVilla

    CallMeVilla

    CallMeVilla

    Well-Known Member

    Joined:
    Feb 9, 2010
    Messages:
    1,651
    Likes Received:
    594
    Honestly, at 13 yo that tank is due to go away. Sediment, corrosion, and a failing PRV ... all point to a replacement. I just replaced a 13 yo tank and more than 50% of the thing was sediment ... it weighed a ton AFTER draining it!

    New ones are more energy efficient, have better thermostats, and easy to install (if you have plumbing skills) ... GO FOR IT.
     
  19. Apr 24, 2013 #19

    montag

    montag

    montag

    Member

    Joined:
    Oct 1, 2012
    Messages:
    19
    Likes Received:
    0
    Thank you CallMeVilla, that's a good point. I think after I have replaced the reducing valve I'll be thinking about that tank replacement as the next project. I think I can do it myself. What tank manufacturer did you go with.
     
  20. Apr 24, 2013 #20

    CallMeVilla

    CallMeVilla

    CallMeVilla

    Well-Known Member

    Joined:
    Feb 9, 2010
    Messages:
    1,651
    Likes Received:
    594
    Most recent replacement was with a Rheem. They wanted a 60 gallon version for the large family in their summer house. It has a "vacation" setting, so its energy use in minimized while they are gone. I receooended turning it off ... but they were fearful about re-lighting every trip.

    You also have to know that tank manufacturers have their metallurgy down to a real science. For a 5-Year tank under normal usage it will die in 5 years +/- one month. Not kidding. I got home after replacing a 5-Year tank one day and my neighbor was hauling a new tank out of his truck. "Yeah, mine died within two months of the five year warranty." he said.

    Be aware! :D

    TANK.jpg
     

Share This Page