main line pressure regulator location?

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by Handiman, Jun 30, 2010.

  1. Handiman

    Handiman New Member

    Apr 18, 2009
    Hello, I recently pressure tested my lines at the faucet nearest the main line from the street. The pressure on the ORBIT gauge reads 45PSI. Isn't the average pressure supposed to be between 55-70PSI.

    Problem is, I can't find the damn pressure regulator anywhere starting at where the line comes in at the street (meter). The irrigation valves look to be the first contact with the water line. Nowhere near the water heater either. Where is the pressure regulator usually located? Local water authority says the pressure is between 70-100PSI in my neighborhood, so there must be regulator somewhere on the line, but where?

  2. Doherty Plumbing

    Doherty Plumbing Journeyman & Gas Fitter

    Jun 22, 2009
    Red Seal Journeyman Plumber & Licensed Gas Fitter
    Penticton, BC
    Your PRV is *usually* located fairly close to your main shutoff valve inside the house. It could be hidden behind paneling or something.

    Sometimes the PRV is located in the ground outside close to the street.

    Some neighbourhoods have a main line PRV that feeds the whole neighbourhood. But this is quite rare.
  3. Sponsor

    Sponsor Paid Advertisement

  4. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Sep 2, 2004
    Retired Systems engineer for defense industry.
    New England
    Are you sure you even have a PRV? It could just be your pressure is low. This could especially be true if you live on a hill or at the end of the line. Does your gauge have a peak reading needle? If so, leave it there overnight and note the high reading (usually late night/early morning when there's little use in the whole system).
  5. Gary Swart

    Gary Swart In the Trades

    Sep 1, 2004
    Yakima WA
    If you have a PRV, it should be after the irrigation system branches off the main line. The only things on the irrigation line would be the back flow device and the zone valves. 45 PSI is fine for you house pressure. It could be higher, but everything will work just fine with 45 PSI. A PRV should be located just after the main line enters the house and before the main shutoff valve and be in easy access for adjustment and replacing. Operative word here is "should". Sometimes things are not done as they should be. I suspect you do not have a PRV and the city is not giving you accurate numbers about what pressure their main line actually has. It may be that once that line carried 55 to 70 PSI but no longer does. If that was the pressure when the house was originally plumbed, it is most likely that no PRV was deemed necessary as while 70 PSI is a bit high, it is not excessively high.
  6. hj

    hj Moderator & Master Plumber Staff Member

    Aug 31, 2004
    Cave Creek, Arizona
    IT would be WHEREVER the installer wanted to put it. I have seen them buried underground 1', 2', and more, from the water meter. They are also installed near the house or in the exposed piping inside the house. I have even found multiple PRVs when an installer did not know there was an existing one which had failed so he installed another one nearer to the meter.
Similar Threads: main line
Forum Title Date
Plumbing Forum, Professional & DIY Advice Main Water Line Leak Aug 10, 2017
Plumbing Forum, Professional & DIY Advice Advice needed......Possible main line clog. Aug 7, 2017
Plumbing Forum, Professional & DIY Advice Main line extension, need advice Jul 25, 2017
Plumbing Forum, Professional & DIY Advice Main Waste Sleeve placed in line with wall instead of just before the wall Jun 25, 2017
Plumbing Forum, Professional & DIY Advice What is minimum distance between top of washer standpipe and main drain line? Jun 19, 2017

Share This Page