Live in a 10 unit condo built around 1986. Each condo has its own PRV and shut off valve. About 2 years ago HOA installed a shut off and PRV for the building. Water pressure immediately decreased to the point residents would have to flush toilet twice. About a year after installation the water pressure went back up to normal (between 50-70 psi). At the same time the pipes in my unit started pounding. It has been a year and the HOA wants to deny there is a problem. Have found out from that the plumbing company who installed the PRV and shut off for building did so without a permit. Was told if they had, never would have passed inspection. Have also been told that the PRVs in the individual units had started going bad and that what needed to happen was that the individual condo PRVs needed to be fixed or disconnected. Also, have been made aware that Thermal Expansion Tank needed to be added either to the building or individual condos. My question is, in your experience would the pressure and pounding in the pipes most likely be coming from the PRVs back to back and fighting each other or no having a Thermal Expansion or both. The plumbuer said he put installed a special PRV for the building that would work with individual condo PRVs. A plumber told me that was not possible, that you can't have a PRV on the building and individual condo PRVs. Does anyone know of a special PRV for this type of situation?
PRV and Shut Off Valve Installed on Condo
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If each unit has a PRV then each unit needs to have a thermal expansion tank.
Thanks. Is there a problem with putting a PRV on the Building and also having them in each unit. One plumber told me they fight each other. I guess what I am asking is do I have another issue here besides the thermal expansion tank?
Call you water utility provider. They maybe able to tell you what the water main pressure is in that area. A few places I have experience that the supply pressure was very high. A high range prv's is installed near the meter. Then individual meters at each unit. The unit prv' were failing because the main was excessively high.
How a typical PRV works.
It has a spring pushing against a diaphragm holding the valve open
That spring sets the desired pressure.
The outlet side pressure of the prv pushes against diaphragm and spring. When desired set pressure of the spring is equal or greater than the spring pressure it closes the valve. any drop in outlet line pressure the spring pushes valve open.
So if the common PRV was set at 50 psi and the unit PRV set at 60 psi, the unit PRV would have no function. It would remain open until the common one failed.
Now it May cause a problem if both are set to about the same pressure.
Common PRV set to 50 for 10 units. with several units pulling water at the same time and depending on the size of the common line could cause a significant water flow problem. Maybe even a noisy PRV
How a typical PRV works.
It has a spring pushing against a diaphragm holding the valve open
That spring sets the desired pressure.
The outlet side pressure of the prv pushes against diaphragm and spring. When desired set pressure of the spring is equal or greater than the spring pressure it closes the valve. any drop in outlet line pressure the spring pushes valve open.
So if the common PRV was set at 50 psi and the unit PRV set at 60 psi, the unit PRV would have no function. It would remain open until the common one failed.
Now it May cause a problem if both are set to about the same pressure.
Common PRV set to 50 for 10 units. with several units pulling water at the same time and depending on the size of the common line could cause a significant water flow problem. Maybe even a noisy PRV
journeyman
the professional
by putting a backflow on the bldg. you have created a closed water system so the thermal expansion can not get pushed back t the city. expansion tanks absorb the thermal expansion
I missed something . What back flow?
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Your post on the other thread didn't have as much detail to it and left the impression that you were doing an installation yourself. It's nice to see that you stopped by again for more opinions and added some insight as to what's going on.
I would just like to summarize what has been said before I add my thoughts.
If each unit has it's own water heater, a thermal expansion tank is needed for each unit having a regulator.
If the building has a central boiler and/or holding tanks then the building needs a central thermal expansion tank.
If the building pressure from the street is high, the building needs a PRV to protect the common plumbing system. The individual units should then have pressure regulators installed as needed and adjusted accordingly.
Each unit could have different pressure depending on elevation and distance from the main domestic water regulator.
"About a year after installation the water pressure went back up to normal (between 50-70 psi). At the same time the pipes in my unit started pounding." This gives me impression that the PRV in your unit failed and the new building PRV has the building running at 50-70 psi. A failed regulator can cause a banging or loud rattling when water is used.
The PRV for the building may have been necessary but made the individual PRVs redundant and some may need to be removed, again that depends on each unit's pressure and location.
The 'special' PRV that was mentioned could be for pressure fluctuations (spikes and drops) and are common in commercial buildings. See image.
In my experience with condos and HOAs, your individual PRV is yours and you can remove it or repair it yourself unless there are contract restrictions with the HOA. If you or a plumber that you hire test your pressure and it is normal without the PRV you might not be allowed to remove it because of liability for flooding if the main PRV were to fail and your unit were to flood others.
Sounds like quite the conundrum.
This is what the HOA needs to do. Have a plumber test incoming pressure before the building PRV and see if the PRV is even necessary. If it is needed, set it to maximum allowed pressure for the common plumbing system. Then the plumber needs to check every unit to see how they are affected and install, repair or remove to make each unit operate normally. It's going to take time and money from you or the HOA or both to solve this issue.
I'm not a lawyer by any stretch of the imagination, but in most condo contracts there is a clause that states that management or the HOA can not make repairs, modifications or additions that negatively impact the individual owner's property. Additionally, upgrades for codes and safety that cause problems in your unit may be their responsibilty.
Example; A friend of mine had a condo and it was determined that the original fire suppression system piping was inadequate and had to be upgraded before owners were allowed to sell their properties. Management was responsible for the upgrades and the repair company cut out drywall and did their work. Drywall was replaced in the common areas, but the individual owners were told that they had to pay for the drywall in each of their units to be repaired. It took some fighting, but the condo association had to make all units as they were before. Just throwing that out there as food for thought.
HOAs can be a real PIA.
I would just like to summarize what has been said before I add my thoughts.
If each unit has it's own water heater, a thermal expansion tank is needed for each unit having a regulator.
If the building has a central boiler and/or holding tanks then the building needs a central thermal expansion tank.
If the building pressure from the street is high, the building needs a PRV to protect the common plumbing system. The individual units should then have pressure regulators installed as needed and adjusted accordingly.
Each unit could have different pressure depending on elevation and distance from the main domestic water regulator.
"About a year after installation the water pressure went back up to normal (between 50-70 psi). At the same time the pipes in my unit started pounding." This gives me impression that the PRV in your unit failed and the new building PRV has the building running at 50-70 psi. A failed regulator can cause a banging or loud rattling when water is used.
The PRV for the building may have been necessary but made the individual PRVs redundant and some may need to be removed, again that depends on each unit's pressure and location.
The 'special' PRV that was mentioned could be for pressure fluctuations (spikes and drops) and are common in commercial buildings. See image.
In my experience with condos and HOAs, your individual PRV is yours and you can remove it or repair it yourself unless there are contract restrictions with the HOA. If you or a plumber that you hire test your pressure and it is normal without the PRV you might not be allowed to remove it because of liability for flooding if the main PRV were to fail and your unit were to flood others.
Sounds like quite the conundrum.
This is what the HOA needs to do. Have a plumber test incoming pressure before the building PRV and see if the PRV is even necessary. If it is needed, set it to maximum allowed pressure for the common plumbing system. Then the plumber needs to check every unit to see how they are affected and install, repair or remove to make each unit operate normally. It's going to take time and money from you or the HOA or both to solve this issue.
I'm not a lawyer by any stretch of the imagination, but in most condo contracts there is a clause that states that management or the HOA can not make repairs, modifications or additions that negatively impact the individual owner's property. Additionally, upgrades for codes and safety that cause problems in your unit may be their responsibilty.
Example; A friend of mine had a condo and it was determined that the original fire suppression system piping was inadequate and had to be upgraded before owners were allowed to sell their properties. Management was responsible for the upgrades and the repair company cut out drywall and did their work. Drywall was replaced in the common areas, but the individual owners were told that they had to pay for the drywall in each of their units to be repaired. It took some fighting, but the condo association had to make all units as they were before. Just throwing that out there as food for thought.
HOAs can be a real PIA.
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Thanks for the good info, Caduceus. As mentioned, the HOA is refusing to acknowledge there is a problem and I am reminded everytime I hear the pipes which is frequent and annoying. It has been a year since this started. In your opinion, do you think there is signficant damage being done to the pipes? The pipes are polybutelyene and cooper. I had a plumber cut a hole in the ceiling but a stud was in the way of seeing the pipes that are pounding. He said we could end up tearing a lot of dry wall out to find locate the pipes. Decided I had spent enough money for now. The pipes he did see were quite loose. Do you think that because the work was done without a permit that using that info my help light a fire under the HOA?
