(206) 949-5683, Top Rated Plumber, Seattle
Page 2 of 2 FirstFirst 12
Results 16 to 27 of 27

Thread: Pressure regulator install for water hammer

  1. #16
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,633

    Default

    If the water pressure is 80 psi, the pressure regulator would be useless. The 140 psi is being generated inside your system which would be after any PRV you install. The expansion tank, in this case really an "accumulator" would act as a buffer, but since any hammer arrestor works best when it is RIGHT at the source of the hammer, not where you hear it, you will not know if it works until after you install it.
    Licensed residential and commercial plumber

  2. #17
    DIY Junior Member boaterbill's Avatar
    Join Date
    May 2013
    Location
    ne ohio
    Posts
    10

    Default

    Thanks hj,

    Tomorrow I will install hammer arrestor at fill valve on the toilet and another at the front loading washing machine. These two items seem to generate the biggest shock through the system. I'll post the results.

  3. #18
    DIY Junior Member boaterbill's Avatar
    Join Date
    May 2013
    Location
    ne ohio
    Posts
    10

    Default

    I installed Sioux chief arresters at front loader washer and fluidmaster fill valve. After install water hammer was muffled significantly in the body of the tank-less water heater. Replaced the 10 year old rubber washer hoses with stainless braided and water hammer was back as if nothing had changed. Switch back to the rubber hoses and the hammer was still there. Put the new hoses back on and called it a night.
    The hammer noise is inside the tank-less water heater. All the shock waves seem to resonate there.
    I took some pictures of the plumbing layout and will try to post.
    Getting back to the tank-less WH where the noise ( bam, bam, bam ) is coming from. It is at least 12 years old Bosch AQ-125-HX- NG and has never been serviced. Inlet screen has never been cleaned. It still supplies plenty of hot water without any problem. Water supply comes from Lake Erie.

  4. #19
    DIY Junior Member boaterbill's Avatar
    Join Date
    May 2013
    Location
    ne ohio
    Posts
    10

    Default

    Name:  IMG_0234 (480x640).jpg
Views: 153
Size:  35.3 KBName:  IMG_0235 (480x640).jpg
Views: 136
Size:  22.0 KBName:  IMG_0236 (480x640).jpg
Views: 121
Size:  25.4 KBName:  IMG_0237 (480x640).jpg
Views: 133
Size:  27.6 KB

    There is a 1/2" line about 12" above the water meter to a tee going left then down. This 1/2" cold line supplies all the fixtures in the house except the tank-less WH. The tank-less supply line is the vertical 3/4 line out of the meter going up and to the right and loops back out of the tank-less for hot water supply.
    If you close the shut off cold water valve under the tank-less WH there is no water hammer sound when you turn off any cold water fixture.
    In the photo there is a piece of blue tape on the 1/2" supply. Can I replace this elbow with a vertical tee and place a hammer arrester on top there? Would that do and good and what type of an arrester and how large?
    The 3/4" line going vertical out of the meter has a white marker at the elbow going right to the tank-less, can I install something there that would be of any help?

    thanks boater bill

  5. #20
    DIY Junior Member boaterbill's Avatar
    Join Date
    May 2013
    Location
    ne ohio
    Posts
    10

    Default

    My recent update:

    By using the shut-off valve (globe valve) before the meter as a throttling valve I was able to reduce the hammer shock to a 20 psi jump to 100 psi from the city 80 psi. Before it was jumping to 140 psi. Now there is only a faint thump coming from the tank-less WH. Is this an acceptable partial remedy? Will the 20 psi spike still cause damage?

    What I plan to do is replace the shut-off valve (wont completely shut off water flow) I 'm using to throttle the water, with a ball valve. Place a 1/2 globe valve to be used as a throttling valve on the 1/2" line to all cold water fixtures to duplicate current partial remedy. Then add small expansion tank on 3/4" line heading to the tank-less WH in hope of eliminating all the water hammer.

    All comments appreciated,
    boaterbill

  6. #21
    Jack of all trades DonL's Avatar
    Join Date
    Mar 2011
    Location
    Houston, TX
    Posts
    3,644

    Default

    Using a Valve like that will only throttle the volume and not the pressure.

    Some Valves want to be opened or closed, and may leak in a different position.

    Use whatever works for you.

    You only need 40-50 psi for your house, 60 is nice, so a Pressure regulator is what you need to fix your problem and be done with it.


    Have Fun.
    Last edited by DonL; 05-24-2013 at 11:53 AM.
    Theory only works perfect in a vacuum.

    Cyber Security Protection for Windows C:\ > WWW.WinForce.Net

  7. #22
    DIY Junior Member boaterbill's Avatar
    Join Date
    May 2013
    Location
    ne ohio
    Posts
    10

    Default

    Quote Originally Posted by DonL View Post
    Using a Valve like that will only throttle the volume and not the pressure.

    Some Valves want to be opened or closed, and may leak in a different position.

    Use whatever works for you.

    You only need 40-50 psi for your house, 60 is nice, so a Pressure regulator is what you need to fix your problem and be done with it.


    Have Fun.
    Thanks DonL,

    I used a RV camper pressure reducer rated at 40 psi on the front loading washer and the outdoor hose bibb and still got water hammer at the tank-less WH. Throttling the flow so far has produced best results . Water dept said they have not had any customer complaints like this. I think I would put the expansion tank in before the PRV and see what happens per hj.
    The other thought I had was to isolate the problem 1/2" cold water fixture line with a check-valve and a hammer arrestor so the shock wave cannot travel back to the tank-less WH inlet line. Anyone have any thoughts on this? Trying to keep it simple.

    Thanks,
    boater bill

  8. #23
    Forum Admin, Expert Plumber Terry's Avatar
    Join Date
    Aug 2004
    Location
    Bothell, Washington
    Posts
    14,201
    Blog Entries
    1

    Default

    I did a job with water hammer in Sammamish.
    When the neigbor turned their water on and off, it hammered the piping next door.

    They also had a PRV valve before it went up into the plumbing. My solution was to run some PEX piping from the incoming shutoff, and then a 3/4" Mini-restor before the new PRV valve. I wanted to provide hammer protection before the PRV.
    It worked.

  9. #24
    In the Trades Jerome2877's Avatar
    Join Date
    Aug 2009
    Location
    BC
    Posts
    384

    Default

    Not sure what the camper PRV is supposed to do? If you install a PRV on your main supply and some shock arrestors on the laundry supplies , you will probably solve the issue. An expansion tank should be installed with a prv so you can set the pressure on both but I still don't think that you will need one.

  10. #25
    DIY Junior Member boaterbill's Avatar
    Join Date
    May 2013
    Location
    ne ohio
    Posts
    10

    Default

    Quote Originally Posted by Jerome2877 View Post
    Not sure what the camper PRV is supposed to do? If you install a PRV on your main supply and some shock arrestors on the laundry supplies , you will probably solve the issue. An expansion tank should be installed with a prv so you can set the pressure on both but I still don't think that you will need one.
    Thanks Jerome,
    The RV camper PRV is set at 40 psi and installed at the shut-off valve of the washer. There is a hammer arrestor at the washer. So at 40 psi and a hammer arrestor it still generates water hammer. Same scenario at hose bibb+PRV+garden hose+spring loaded nozzle generates water hammer at 40 psi when the nozzle slams shut. Seems like the shock wave needs to be dissipated some where other than the tank-less WH. Maybe expansion tank and no PRV.

    Thanks,
    boaterbill

  11. #26
    In the Trades Jerome2877's Avatar
    Join Date
    Aug 2009
    Location
    BC
    Posts
    384

    Default

    Quote Originally Posted by boaterbill View Post
    Thanks Jerome,
    The RV camper PRV is set at 40 psi and installed at the shut-off valve of the washer. There is a hammer arrestor at the washer. So at 40 psi and a hammer arrestor it still generates water hammer. Same scenario at hose bibb+PRV+garden hose+spring loaded nozzle generates water hammer at 40 psi when the nozzle slams shut. Seems like the shock wave needs to be dissipated some where other than the tank-less WH. Maybe expansion tank and no PRV.

    Thanks,
    boaterbill
    The main reason for water hammer is pressure spikes from quikly closing valves. If the pressure is reduced (meaning on your main comming into the house) Then the spike will also be reduced. The shock absorber may not be able to handle the pressure spike because the pressure is too high. So I would first start with a PRV (set to about 60 psi) and if that doesn't do it then add the expansion tank.

  12. #27
    Jack of all trades DonL's Avatar
    Join Date
    Mar 2011
    Location
    Houston, TX
    Posts
    3,644

    Default

    Quote Originally Posted by Jerome2877 View Post
    So I would first start with a PRV (set to about 60 psi) and if that doesn't do it then add the expansion tank.

    That is what I would do. PRV on the Input to the House.

    Chances are, You can use the California Flow Regulating Washer Discs for the rest of the problems.


    It is not Rocket Science, but theory still applies.
    Theory only works perfect in a vacuum.

    Cyber Security Protection for Windows C:\ > WWW.WinForce.Net

Similar Threads

  1. Water hammer after pressure balance valve install
    By takatsu in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 8
    Last Post: 03-02-2013, 11:40 AM
  2. Changing water pressure on house pressure regulator.
    By kskier in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 2
    Last Post: 04-30-2010, 09:20 AM
  3. Pressure Regulator install Q
    By BrianPlumBrian in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 4
    Last Post: 05-04-2007, 06:04 AM
  4. Where to install a pressure regulator
    By Guest in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 12
    Last Post: 01-25-2006, 04:14 AM
  5. Where to install pressure regulator?
    By Vitaliy in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 1
    Last Post: 09-01-2005, 08:13 PM

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
  •