Low water pressure

[Anonymous]

I am on a municipal water system and my water pressure is about 45 psi with nothing running. Open one faucet and it drops to 37. Open a tap and the tub and it drops to 15. The inside of the house is 1/2″ PVC. Outside is 1″ iron.

My questions are – Can I put a diaphragm pressure tank directly on my water supply line and will it help?

Thanks

[SylvanLMPParticipant]

How old is the “iron” pipe that is your water main supply?

You may want to replace it with “K” copper tubing.

Ferrous metal sometimes gets deposits on the internal pipe walls and thus causes a restriction where you lose volume and then a pressure drop.

Normally according to good plumbing practices if your replacing Iron piping and replace it with copper you can reduce it one commerical size BUT in this case I would replace in kind with a 1″ coppper tubing, taking all precautions with the soil conditions back filling etc.

[hjParticipant]

If your inside pipe is actually 1/2″ PVC, then the opening in the pipe is relatively small, so the pressure drop could be a combination of obstructed steel service and undersized inside piping. Also PVC is not legal inside a house and should never be used for hot water piping.

[SylvanLMPParticipant]

HJ IM so sorry to differ with you BUT certain codes DO ALLOW cold water piping to be PVC inside the buiding with certain restrictions for example.
PVC shall be accessable OR exposed CW only then of course CPVC is also allowed on hot water lines But again depending on local codes.

Personaly I would never use PVC unless it was required because of the acid system I was installing and no other material would work.

HJ read the NFPA which is now allowing “plastic” for sprinkler (fire supression) work for certain applications.

Amazing huh

[Radams2ndParticipant]

Thank you all for the replies.
In the meantime, I have gotten hold of the city water guys and had them come out. Turns out they could remove our meter so I could check the flow from the main to it. The flow from the main to it was great. So I have an obstruction between the meter and the house. I am planning on putting in new pipe from there to the house soon.

Thanks.

[Author]

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